Hazrat ‘Umar (radhiyallahu ‘anhu) gestured towards the blessed grave of Rasulullah (sallallahu ‘alaihi wasallam) and addressed the person saying, “Do you know who the occupant of this grave is? It is Muhammed (sallallahu ‘alaihi wasallam), the son of ‘Abdullah who is the son of ‘Abdul Muttalib, and Hazrat ‘Ali (radhiyallahu ‘anhu) is the son of Abu Taalib who is the son of ‘Abdul Muttalib. Hence, when Hazrat ‘Ali (radhiyallahu ‘anhu) is the cousin of Rasulullah (sallallahu ‘alaihi wasallam), you should not speak anything but good regarding him, for if you anger him then you will cause pain to Rasulullah (sallallahu ‘alaihi wasallam) in his grave.” (Fadhaa’il-us-Sahaabah lil-Imaam Ahmed #1089)

In the above incident, it is evident that Hazrat ‘Umar (radhiyallahu ‘anhu) had the utmost respect and love for Hazrat ‘Ali (radhiyallahu ‘anhu). It is for this reason that when a person began to speak ill of Hazrat ‘Ali (radhiyallahu ‘anhu), Hazrat ‘Umar (radhiyallahu ‘anhu) could not tolerate it and immediately rose in defense of Hazrat ‘Ali (radhiyallahu ‘anhu).

May Allah Ta‘ala bless us all with the true love and respect of the Sahaabah (radhiyallahu ‘anhum).