Narrated 'Abdullah bin Mas'ud:
"Allah has not created in the heavens nor in the earth what is more magnificent than Ayat Al-Kursi." Sufyan said: "Because Ayat Al-Kursi is the Speech of Allah, and Allah's Speech is greater than Allah's creation of the heavens and the earth." (DE)
English reference (DE): Vol. 5, Book 42, Hadith 2884 (DE)
Arabic reference (DE): Book 45, Hadith 3122 (DE)