Ayatul-Kursi and Confirming Proofs of at-Tawheed

Imam Muslim collected a hadith in his Saheeh on the the authority ob Ubay bin Ka’b (radhiallahu ‘anhu) that he said “Allah’s Messenger (sallallahu ‘alayhi wa ‎sallam) said, ‘O Abul-Mundhir! Do you know ‎which verse from the book of Allah is the ‎greatest? Ubay bin Ka’b said, “I replied, ‘Allah ‎and His Messenger know best’. The Prophet ‎‎(sallallahu ‘alayhi wa sallam) said, ‘O Abul-‎Mundhir! Do you know which verse from the ‎book of Allah is the greatest? Ubay bin Ka’b ‎said, “I said, “Allah! Lâ ilâha illa Huwa (none ‎has the right to be worshipped but He), the ‎Ever Living, the One Who sustains and protects ‎all that exists.” Ubay bin Ka’b said, “He ‎smacked my chest and said, “By Allah! ‎Congratulations, Abul-Mundhir for having ‎knowledge.” ‎ ‎ ‎ Meaning congratulations for this knowledge which ‎Allah has gifted you, facilitated for you, and has ‎blessed you with. The Prophet (sallallahu ‘alayhi wa ‎sallam) swore by Allah exalting this status and ‎emphasizing this ambition. ‎ Among Ubay’s excellent perception and keenness ‎‎(radhiallahu ‘anhu) is that when the Prophet (sallallahu ‎‎‘alayhi wa sallam) questioned him he continued in his ‎search for the verse which is dedicated to clarifying ‎the greatest matter in the Quran, At-Tawheed, an ‎acknowledgement of its confirming proofs, and a ‎mention of Allah’s greatness and perfection which He ‎is deserving solely to be worshipped. This was from ‎the completeness of his understanding and excellent ‎understanding of the religion. ‎ He didn’t cite a verse clarifying praiseworthy ‎etiquettes, subsidiary judgments, past events, ‎horrors of the Day of resurrection or similar to that; ‎rather, ’Ubay selected the verse which is dedicated to ‎clarifying and acknowledging at-Tawheed.