Amen

The Hebrew expression can be translated as "faithful," "certain," "so it shall be, "and "let it be confirmed." Under the law, the truth was to be affirmed in solemn moments - often collectively (Num. 5:22; Deut. 27:14ff; 1 Kings 1:36; Neh. 5:13), or the content of a song of praise was to be confirmed (Neh. 8:6; Ps. 41;72; 89;106). In the New Testament, we find that Jesus says "Truly, truly" 25 times in the Gospel of John (amen in the basic text) in order to give special weight to a statement. Christ Himself is called the "Amen" in Rev 3:14 (cf. Isaiah 65:16: God of faithfulness = God Amen) because God's promises are fulfilled in Him (2 Cor 1:20).