John Gill Commentary Genesis 22:15

"And the angel of Jehovah called unto Abraham a second time out of heaven," — Genesis 22:15 (ASV)

And the Angel of the Lord called unto Abraham out of heaven
the second time .
] The Angel having restrained him from slaying his son, and having provided another sacrifice, which he offered, calls to him again; having something more to say to him, which was to renew the covenant he had made with him, and confirm it by an oath.