Background and Aim: The international law of the seas is based on the strong shoulders of the powerful system of international custom that has been repeatedly cited by international judicial and arbitration authorities. Therefore, in a comprehensive study, it was necessary to study the Customary Rules of delimitation of maritime areas, which have undergone many changes and transformations over the centuries. The present article examines this trend with a brief look at the Customary Rules of delimitation of maritime areas. Materials and Methods: The research method in this paper is descriptive-analytical. Ethical Considerations: Ethical considerations regarding the writing of texts as well as references to sources were observed. Findings: Customary international law has played an important role in the process of forming the international law of the seas and shaping the necessary criteria to evaluate its Rules. The principle of the commonality of the seas, the national authority over the seas, the principle of the freedom of the seas in the Middle Ages, the judgment of the maritime courts and the legal opinions of the maritime dispute resolution authorities are evidence of the Customary Rules governing the seas. If the Customary Rules are so effective in the formation of the Rules of delimitation of maritime areas that need special attention, then the course of its evolution was examined and the impact of Customary Rules on the development of the law of the sea was examined. Conclusion: This article emphasizes that Customary law has not provided a specific method for delimitation that is legally binding or creates a privileged position over other methods.

IntroductionAfghanistan is a  country that shares four waterways (Hirmand, Kabul, Harirud, Amu) with neighboring countries. These watercourses are an important source of water supply in Afghanistan and its neighboring countries. Except for the Hirmand River which has the 1973 treaty as its governing source of legal regulation, the other three water basins of Afghanistan do not have a treaty exploitation system and are considered subject to the Customary Rules. Therefore, any use of these waterways is only possible within the framework of the Customary Rules of international law of the sea. Due to various historical reasons, Afghanistan has not had the opportunity to avail itself of these watercourses. In the last few years, this country has designed and implemented programs to manage and use its water resources. Many of these actions were faced with protests from Afghanistan's neighboring countries. These countries have considered the actions taken by Afghanistan to be in conflict with international law, especially the Customary law governing international waterways. According to the practice of states, and the opinions of international judicial and non-judicial institutions, currently, there are Rules such as reasonable and equitable utilization, the prohibition of incurring serious harm to other countries, and the responsibility to cooperate, which underly the basic and Customary Rules of international law of the sea. The Customary characteristic makes states legally obliged to comply with these Rules regardless of their membership in international treaties. States’ violation of Customary obligations will result in international liability. Without a doubt, Afghanistan, as a member of the international community, will not be exempt from this rule. Research Questions The present research examines the status of the Customary obligations regarding the non-navigational use of international waterways in the legal system and the practical practice of the Afghan government. The research seeks to answer these questions: What is the approach of Afghanistan's legal system towards the international Customary Rules of the sea and do the domestic laws require the government to comply with these obligations or not? What is the practical practice of the government in this case and to what extent are Afghanistan's actions consistent with the international Customary Rules? Research Background As an important source of life and livelihood, the subject of waterways has been of interest to humans forever. The greatest human civilizations are built next to water sources. With the formation of nation-states, the discussion of international waterways and their exploitation by countries was raised. In this regard, many researches have been conducted and published by scholars on how to regulate the use of international watercourses around the world.Although such research was initially centered around the use of navigation, with the increase in population, the climate changes, and the pollution of water resources, non-navigational exploitation and their related topics also attracted the attention of scholars. Regarding the international watercourses of Afghanistan, many researches have been published by different authors both inside and outside of Afghanistan, in different languages.The common denominator of all of these efforts is the focus on contractual obligations, management, and the protection of water resources. Therefore, an important i.e., international Customary obligations of Afghanistan and its practice and performance in this area has been neglected. However, some authors have mentioned some of these obligations in their research. For example, we can refer to works such as the research  of Mr. Jamshid Momtaz titled “The legal system of the middle East watercourses”, “Ali Raghanabi: The legal principles governing the international rivers, with an emphasis on the Hirmand River”, “Nusratullah Afzali: The principles governing the international watercourses with an emphasis on the Harirud river”, and “Mrs. Sara Naqshband: International Practices in the Settlement of International River Disputes”. Within Afghanistan, in the last few years, research has been carried out in the field of Transboundary Rivers. The major parts of these research papers have been carried out by the Doran Institute, which is a private research institute. This research center has so far published two articles in this area (Amu and Kabul) and besides these, publishes a journal about the waters of Afghanistan, the first issue of which was published in 2015. This research focuses on the capacities of the mentioned areas, the capabilities and challenges of their use, and the climate risks that threaten these waters; it briefly refers to the legal aspects of using these waters. however, it has not been specifically and comprehensively addressed. DiscussionArticle 7 of Afghanistan’s Constitution recognizes the government’s responsibility to comply with the United Nations Charter, the Universal Declaration of Human Rights, and other treaties that Afghanistan has accepted, but it does not make any reference to international Customary obligations. Of course, this does not mean that Afghanistan does not accept Customary international obligations. the obligation to comply with the UN Charter (based on Articles 1 and 2 and other principles of the Charter) is not limited to treaties, and includes obeying all binding sources of international law. The constitution, especially its seventh article, has stated the obligations that need to be approved by the parliament (National Council) and approved by the president. Customary international obligations are usually entered into national systems through automatically and informally and do not require a special process for ratification andapproval. The study of Afghanistan's legal practice, including the study of the past constitutions (1980 and 1987), in which, in addition to treaties, Afghanistan's obligations to other accepted principles and Rules of international law are set out, supports this claim.This is why the Afghanistan transboundary water policy, which was approved by the Council of Ministers in 2015, mentions Afghanistan's responsibility to comply with the international Rules and regulations in the operation of transboundary waters in its sixth chapter. International Rules and regulations include contractual and Customary Rules.The practice of the Afghan government in the exploitation of common waterways is in line with its responsibility to act by these Rules. The signing of a treaty with Iran (in 1973) and an agreement with the Soviet Union in the field of utilization of the Amu River (in 1958 and 1964) indicates that this country considers itself bound to international obligations in this field. Conclusion The Afghan constitution is silent on its international Customary obligations. nevertheless, the emphasis on compliance with the United Nations Charter in its seventh chapter also includes complying with the Customary Rules. The legal and practical practice of the Afghan government shows that this country considers itself obliged to comply with these obligations not only as a  member of the international community; but also according to its domestic laws. However, examining the degree of compliance of this country's actions in the use of international waterways with its international obligations requires examining all the related factors. Without access to the relevant information, it would be very difficult to consider these actions in violation of these obligations. However, the principle of responsibility to cooperate obliges the Afghan government to take appropriate measures to deal with these protests within the framework of international law.

The word "Customary Knowledge" is used to show a degree of preferred belief in which one should have complete trust and great belief to an object while he/she does not reach to absolute certainty (yaqiin) -in logic and philosophic sense. In this stage of belief we may reasonably confront with a contrary contingency but the wise people do not rely in this contingency and set it aside. They treat and recognize the Customary knowledge as knowledge in logic sense and invoke to it in all aspects of their life In inferring shariah Rules, Islamic jurists usually and generally seek for logic knowledge and specific conjecture (zann e khaas) as the means of inferring the Rules. However, they believe that in the process of inferring Islamic Rules they can invoke to Customary knowledge. Islamic legislature (divine shaare) do not deny the way of the wise people in reliance on Customary knowledge and permits to infer shariah Rules on the base of this means of inferring.

Contrary to the Statutes of the International Criminal Tribunals for the Former Yugoslavia and Rwanda, which specify only the jurisdiction of those tribunals and the Applicable Law should be sought elsewhere, Article 21 of the Rome Statute sets out the applicable law by the International Criminal Court (ICC). A noteworthy point in Article 21 is that there is no explicit reference to Customary International Law as a legal source applicable by the International Criminal Court, then some consider this silence to be an end to the role of Custom as a legal source in the ICC's setting and International Criminal Law in general. On the other hand, some still believe that the ICC can invoke Customary International Law as a substantive source of law. This article, after referring to other procedures of the International Criminal Tribunals and expressing opposing and agreeing views in International Criminal Law, finally shows that in special cases, invoking custom is the only way to exercise criminal jurisdiction over certain crimes and establish Individual Criminal Responsibility within the framework of the Statute of the International Criminal Court.

Most jurists believe that the Rules that are implemented in society, including criminal law, commercial law, banking, etc., must be completely in accordance with the Rules set forth in the books of jurisprudence or must be under one of those titles in order to be valid. Based on the findings of this research - which has been written in a descriptive-analytical method -, not only the validity of transactions does not depend solely on their concurrence with the Shāri‘ (the legislator) and the Shāri‘s approval of them so as, thereby, the validity of new transactions is denied; rather, it cannot even be accepted that every transaction and law that was valid and approved by the legislator in the era of Revelation is necessarily valid today. In other words, to imply tradition and hadith on the approval of a transaction is not a criterion for its validity in other times and places. Rather, laws - whether approved or newly raised - will be valid under two conditions: one that is in accordance with existing conditions and requirements, and the other that is not in conflict with the purposes and generalities of Shari’a. In this case, they will be valid for the same time and the same society.

Customary Criminal Code (1916) is the first substantial code in Iranian criminal law. This Code is ratified about 38 years after Counte Code (1879). Its importance is that it makes the substructures of its post criminal codes. This Code is very important due to new division of crimes, penalties and explanations of Counte Code which was unprecedented. These regulations show Iranian criminal law developments and Iranian legal social culture in 100 years ago. Many of current criminal law organizations go back to even pre-constitutional period. Recognition of the typology of crime and punishment in Customary penal code is of great importance. So that, this law has many effects in criminalization, the new division of crimes, determination of various penalties, especially imprisonment, identification of different institutions and principles predictions such as the principle of legality of crimes and punishments on the penal codes after itself (from 1304 to 1392). The crimes divided into three groups of crimes against persons, property and security the first time was done by this law and the sentence of imprisonment organized and widespread in this way entered into Iran Criminal Law System. In the present article explain the penological analysis of Customary Penal Code and the statement of the penals system of this law and penological evaluation based on the functions of punishment.

Common international waterways have special importance and status in terms of international law and relations. Undoubtedly, one of the most important challenges of the last century of international institutions is to try for more coordination between States with common water resources and fair allocation of these resources among them. Familiarity of the States with international customs and laws on how to exploit shared water resources will lead to optimal management and reduce tensions in this area. In this regard, several international treaties and agreements have been prepared with the efforts of international organizations and institutions. In addition, many Customary laws have been appeared in this regard at the international level.Despite the great importance of the issue, the challenge of using international waterways  has not yet been managed and planned by an international binding agreement or law, although with the passage of time, public understanding for international participation to solve resource problems Common blue has increased; But the world community has not yet reached a suitable conclusion on an international document that can be agreed upon for the management and protection of common water resources.Until now, various laws, treaties and resolutions have been approved regarding the joint exploitation of common water resources, but due to the existence of problems and ambiguities in some of the articles of these laws, none of these laws are used as a reference law. One of the important reasons for that is the existence of different doctrines and attitudes towards environmental law and its philosophy.According to the Helsinki Laws of 1996, all countries located along the river have equal rights to use water resources, and no country has the right to use river water if it causes damage to other countries along the river. In the 1997 Convention on the Rights of Non-Navigational Uses of International Waterways, many legal principles raised in international environmental law, such as "the principle of rational and fair exploitation and use of water and the principle of prohibiting damage to the territory of the state Other" and the principle of "international cooperation" have been formulated and presented.In terms of research, the articles written in this field are mostly in English. One of the most important works done in Persian language in this field is an article written by Mr. Shuli, Watan Feda and Mrs. Sarkar Khanum Arideh entitled "Examination of the theories and legal provisions of water sharing in the laws of international treaties on border waters" The article examines international treaties on border waters, which is very valuableConsidering the important differences and problems of the Islamic Republic of Iran with its neighbors regarding common waterways and considering the severe water shortage, the most important achievement of this article is the pathology and finding ways to optimally use international regulations, laws and obligations to prevent It is a violation of the right of our country and also to refrain from any tension with the neighbors in this regard. The most important hypothesis of the article is about this axis: "Customary obligations of countries and approved international conventions on the issue of international waterways are the only way to resolve the disputes of neighboring countries in this area. The purpose of this article is to analyze the existing international laws, customs and treaties on how countries use common water resources. Based on the findings of this study, compliance with regulations and treaties by countries will lead to optimal management and reduce tensions in this area.