All the promises of God find their Yes in him. That is why it is through him that we utter our Amen to God for his glory. (2 Corinthians 1:20)
Prayer is a response to promises, that is, to the assurances of God’s future grace.
Prayer is drawing on the account where God has deposited all his stores of future grace.
Prayer is not hoping in the dark that there might be a God of good intentions out there. Prayer banks on the promise of God, and goes to the bank every day and draws on stores of future grace needed for that day.
Don’t miss the connection between the two halves of this great verse. Notice the “that is why”: “All the promises of God are Yes in Christ. That is why (therefore) we pray Amen through him, to God’s glory.”
To make sure we see it, let’s turn the two halves around: When we pray, we say Amen to God through Christ, because God has said a decisive Amen to all his promises in Christ. Prayer is the confident plea for God to make good on his promises of future grace — for Christ’s sake. Prayer links our faith in future grace with the foundation of it all, Jesus Christ.
Which leads to the final point: “Amen” is a full and precious word in times of prayer. It doesn’t mean primarily, “Yes, I have now said this prayer.” It means primarily, “Yes, God has made all these promises.”
Amen means, “Yes, Lord, you can do it.” It means, “Yes, Lord, you are powerful. Yes, Lord, you are wise. Yes, Lord, you are merciful. Yes, Lord, all future grace comes from you and has been confirmed in Christ.”
“Amen” is an exclamation point of hope and warranted confidence after a prayer for help.