Rasulullah (sallallahu ‘alaihi wasallam) himself highlighted this, as reported in the following Hadith:
عن عويم بن ساعدة رضي الله عنه أن النبي صلى الله عليه وسلم قال : إن الله اختارني واختار لي أصحابا (مجمع الزوائد 9/738)
Hazrat Uwaim bin Saa’idah (radhiyallahu ‘anhu) reports that Rasulullah (sallallahu ‘alaihi wasallam) said, “Allah Ta‘ala chose me (to be the final messenger) and chose for me my Sahaabah (as my supporters).”
It is reported in the Mubaarak Hadith that Allah Ta‘ala looked at the hearts of the creation. He found the heart of Nabi Muhammad (sallallahu ‘alaihi wasallam) to be the best of hearts. Therefore, he selected him for Himself and sent him with His message. Thereafter, Allah Ta‘ala looked at the hearts of the rest of the creation after selecting Nabi Muhammad (sallallahu ‘alaihi wasallam). He then found the hearts of the Sahaabah (radhiyallahu ‘anhum) of Rasulullah (sallallahu ‘alaihi wasallam) to be the best hearts (from the entire creation after the Ambiyaa ‘alaihimus salaam). Hence, He divinely selected them as the supporters of His Nabi (sallallahu ‘alaihi wasallam) who will fight against the kuffaar for the course of His deen.” (Musnad-e-Ahmed 6/84)