Sayyiduna Abu Hurairah (may Allah be pleased with him) narrates: Once the Prophet Muhammad (peace and blessings be upon him) passed by Abdullah bin Ubayy. He was sitting under the shade of a dense tree at that time. He said: Ibn Abi Kabsha (i.e., the Prophet Muhammad, peace and blessings be upon him) has stirred up dust upon us. His son Abdullah said (to the Prophet, peace and blessings be upon him): By the One Who has honored you! By the One Who has revealed the Book to you! If you wish, I will bring you his head. The Prophet Muhammad (peace and blessings be upon him) said: No. Treat your father well and serve him.

Abu Kabsha was the maternal grandfather of the Prophet Muhammad (peace and blessings be upon him). He had traveled to Syria. He liked the religion of the Christians, and when he returned to the Quraysh, he began to preach Christianity. The Quraysh became displeased with him because he was presenting a religion different from theirs. That is why the Quraysh used to taunt the Prophet Muhammad (peace and blessings be upon him) in reference to him and attributed him to Abu Kabsha. By this, the Quraysh meant that the Prophet Muhammad (peace and blessings be upon him) had also brought a new religion different from that of those people, just as Abu Kabsha had brought a religion different from theirs.