"In 1 Peter 1:10-12, the apostle is speaking of salvation, and there I read as follows:- Of which salvation the prophets have inquired and searched diligently, who prophesied of the grace that should come unto you: searching what, or what manner of time the Spirit of Christ which was in them did signify, when it testified beforehand the sufferings of Christ and the glory that should follow.
Unto whom it was revealed, that not unto themselves, but unto us they did minister the things which are now reported unto you by them that have preached the gospel unto you with the Holy Ghost sent down from heaven; which things the ANGELS DESIRE TO LOOK INTO.
What things do the angels desire to look into?-
The salvation of God when it is preached with the Holy Ghost sent down from heaven.
The Greek word for "desire," here means "to set one's heart upon."
And the Greek word for "look into" means, "to stoop to a thing in order to look at it; to look at with head bowed forwards; to look into with the body bent; to look carefully into, to inspect curiously-of one who would become acquainted with something." Such is the attitude of the angels toward the subject of salvation."
A.T.Jones