Narrated 'Amr bin Shu'aib:
From his father, from his grandfather, that the Messenger of Allah (ﷺ) said during his Khutbah: Fulfill the allegiances sworn in Jahiliyyah for it - meaning Islam - does not add to them except in gravity. And do not initiate new allegiances in Islam.
[He said:] There are narration on this topic from 'Abdur-Rahman bin 'Awf, Umm Salamah, Jubair bin Mut'im, Abu Hurairah, Ibn 'Abbas, and Qais bin 'Asim.
[Abu 'Eisa said:] This Hadith is Hasan Sahih.