Musnad Ahmad 652:18

Zayd ibn al-Hubab narrated to us, Husayn ibn Waqid narrated to me, Simak ibn Harb narrated to me, from al-Nu’man ibn Bashir, who said: I heard the Prophet, peace and blessings of Allah be upon him, saying: "Indeed, Allah, the Almighty and Majestic, and His angels send blessings upon the first row, or the first rows."