Musannaf Ibn Abi Shayba 21:726

'Abbad ibn al-'Awwam narrated to us, from Ibn al-Musayyib, from his father, who said: When the deceased is placed in his grave, do not say "In the name of Allah" (Bismillah), but say: "In the way of Allah, and upon the creed of the Messenger of Allah, may Allah bless him and grant him peace, and upon the creed of Abraham, inclining toward truth, and he was not of the polytheists. O Allah, make him firm with the firm word in the Hereafter. O Allah, place him in better than what he was in. O Allah, do not deprive us of his reward, and do not try us after him." He said: And this verse was revealed regarding the occupant of the grave: "Allah keeps firm those who believe, with the firm word, in the worldly life and in the Hereafter."