"Amen" is a Hebrew word that means "truly" or "so be it." When we say this at the end of a prayer, we are agreeing with the prayer. We're asking God to please let it be as we have prayed.
What does 'amen' mean? Why do we end prayers with 'amen'?
The Bible uses "amen" in both the Old and New Testaments. Almost half the occurrences appear in Deuteronomy as God announces punishments for specific sin (Deuteronomy 27:15–26). The people respond by saying "Amen" in agreement with God's justice and in acquiescence to His ways.
In the Old Testament, "amen" is linked with praise. For example, in 1 Chronicles 16:36, "… all the people said, 'Amen!' and praised the Lord." Nehemiah 5:13 and 8:6 similarly link saying "amen" with praising the Lord.
In the New Testament, letters often use "amen" in connection with praises to God, including letters from John, Jude, Peter, and Paul. Here is one example: "Now to him who is able to do far more abundantly than all that we ask or think, according to the power at work within us, to him be glory in the church and in Christ Jesus throughout all generations, forever and ever. Amen" (Ephesians 3:20–21).
When Christians pray and end their prayers with "Amen" they are asking that God would hear and grant their prayer. "Amen" is not a magical word nor a plea to conform God to our wills. Rather, it is a statement of confident hope that we make to a God who invites His children to come to Him in prayer (Hebrews 4:14–16; 10:19–23; Matthew 7:7–11). We trust that He knows what is best and desire that His will be done (Matthew 6:10; 26:39). When we pray according to God's will, we can be confident that He will grant our requests (John 14:12; 1 John 5:14).
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Truth about Prayer