Musnad Abu Ya'la al-Mawsili 18:1

Abu Bakr ibn Abi Shaybah narrated to us, Khalid ibn Makhlad narrated to us, from Ali ibn Hashim, from Ash'ath, from Muhammad ibn Sirin, from al-Jarud al-'Abdi, who said: I came to the Prophet, may Allah bless him and grant him peace, to pledge allegiance to him. I said to him: "On the condition that if I leave my religion and enter into your religion, Allah will not punish me in the Hereafter." He said: "Yes."