From Sahih Bukhari (Hadith 7455):
Narrated Ibn `Abbas:The Prophet (ﷺ) said, "O Gabriel, what prevents you. from visiting us more often than you do?" Then this Verse was revealed:--'And we angels descend not but by Command of your Lord. To Him belongs what is before us and what is behind us..' (19.64) So this was the answer to Muhammad
Reference: Bukhari 7455