It is narrated that the Prophet ﷺ told Abdullah ibn Abdullah Ibn Ubayy of his father's boast:

"If we return to Al-Madinah, indeed the more honorable will expel therefrom the meaner." Abdullah responded, asserting, "You are indeed the honorable one, and he is the meaner one."

He then stood at Al-Madinah's gate with a sword, preventing his own father from entering until the Prophet ﷺ gave him explicit permission to step aside.

This demonstrates the extraordinary height of the Companions' loyalty.