The cornerstone of the Prophetic mission was to preach Divine Unity. All the Prophets concentrated on this basic principle, as stated in the Qur’anic verse:

God sent many Prophets during human history. There is no people to whom a Prophet was not sent. The agreement of all the Prophets, who came at different times and in different places, on a single basic principle demonstrates, without doubt, that they did not speak or act on their own, but taught the Message they received from God. The disagreement of philosophers and thinkers – no matter how great they may be – depending on their own intellect and findings, and the differences of opinion frequently observed even within a philosophical or sociological school vis-à-vis the agreement and accord among the Prophets, undeniably prove that while the former propagate the outcome of their defective reasoning, the latter were taught by a Single, Eternal Teacher, God. This fact is also a strong evidence of Divine Unity, the principle on which they unanimously concentrated their mission, as declared by the Last of them:

The most meritorious of the words spoken by me and the Prophets before me is: There is no god but God, He is One, having no partners.