Semantic of Divine attributes and names is one of the key doctrinal issues in philosophy of religion, philosophy, kalam, mysticism and contemporary scholars. This topic often brought up as assimilation and purification in the field of Islamic Sciences. Ibn Arabi knows purification and assimilation are exactly the same. In his eyes, the similarity between Divine attributes and possibilities is that Divine attributes are His manifestations and possibilities attributes are appearances of His attributes. In his idea, assimilation is in existence itself and purification is in limits of manifestations. But Molla Sadra based on emanationism and "cause and caused cognation" knows creature’s perfections completely in God. Therefore, with demonstrative approach based on three fundamental principles in this school (fundamental reality of existence, content participation in concept of existence and analogicity in reality of existence) believes in content participation and analogicity in Divine existence and attributes and with this way, he tries to get rid of absolute assimilation and divesting God of His attributes. Allame Tabatabaei in some positions expresses Molla Sadra’s theory but in other positions he knows the definitions of attributes non-compliance with God due to the fact that it is impossible to take away limitations such as lack of sameness among attributes from definitions of attributes. We will see by criticism and description of these approaches that all of them are based on ontological foundations that don’t give permission to put assimilation aside completely, however they deny absolute assimilation. But Allame’s second approach denies semantic assimilation