The Gospel is the Power of God to Salvation
Source: TTT
Romans 1:16
I am not ashamed of the gospel, because it is the power of God for salvation to everyone who believes, first to the Jew, then to the Greek.
1 Corinthians 1:18
For the message of the cross is foolishness to those who are perishing, but to us who are being saved it is the power of God.
1 Thessalonians 1:5
because our gospel came to you not only in word, but also in power, in the Holy Spirit, and with great conviction—just as you know we lived among you for your sake.