'Concerning' in the Bible

Concerning this salvation, the prophets who prophesied about the grace that would come to you searched and carefully investigated.

It was revealed to them that they were not serving themselves but you. These things have now been announced to you through those who preached the gospel to you by the Holy Spirit sent from heaven. Angels desire to look into these things.

and the Lord God sanctify in your hearts. And be ready always for defence to every one who is asking of you an account concerning the hope that is in you, with meekness and fear;

Beloved, think it not strange concerning the fiery trial which is to try you, as though some strange thing happened unto you: