If someone defending a claim says: "I have paid the creditor the credit," though the confession is not literally compound, its meaning consists of two parts: one expressly indicated which is "paying the debt" and the other implicit meaning which is "being in debt". Now the question is whether in such cases - Conceptual complex confession- the speaker admits his debt and is liable to pay the debt, unless he proves to reject the creditors claim, or no confession to debt is made. In other words, is it required, in such cases, to accept divisibility or indivisibility of confession? Famous lmamite jurisprudents have asserted the divisibility of the confession. Yet, the famous theory is focused on in this article and it seems that the opinion is not accepted in Iranian Civil Code. One of the results of this research is that, considering the Civil Code, the legal principles and judicial precedents and some of the authentic jurisprudent opinions, the indivisibility of the confession is generally accepted and even no objection is seen in the lawyers' views and the case law. In French legal system as well as those of the Islamic countries, according to legal texts, the lawyers' opinions and also judicial precedents, the rule of the indivisibility of the confession is accepted and, with the exception of the rare cases, it is prevented to divide the confession to the detriment of the confessor. However, in the legal system of these countries, unlike that of Iran, there is a distinction between judicial and non-judicial confession and the indivisibility rule is limited to judicial confession and in non-judicial confession, decision on the (in) divisibility is left to the judge to be made according to the general rules of evidence.