Sahih Bukhari, Hadith: Q7417, (21) Chapter. The Statement of Allah: “Say (O Muhammad (p.b.u.h.)): ‘What thing is the most great in witness?’ Say: ‘Allah…’ ” (V.6:19)

صحيح البخاري

Sahih Bukhari

كتاب التوحيد

The Book of Tauhid (Islamic Monotheism)

باب: {قل أى شيء أكبر شهادة قل الله} :

(21) Chapter. The Statement of Allah:“Say (O Muhammad (p.b.u.h.)): ‘What thing is the most great in witness?’ Say: ‘Allah…’ ”(V.6:19)