Psalm 22:25 My praise shall be of thee in the great congregation: I will pay my vows before them that fear him.
David praises the Lord in public, in the great congregation. He pays his vows, makes a thankoffering, in front of the gathered believers. He is not quiet and shy about his faith relationship with the Lord. He wants the world to know he believes, loves, and praises the Lord for His great goodness and salvation. He wants his fellow faithful believers to know he will keep his promises.
Our response to the gospel of salvation is to do the same thing, every week. By worshipping in regular church services and by fellowshipping in group Bible study we praise the Lord and keep our vows. We do not hide our faith under a bushel, but we let our light shine so that the world knows how great and good our God is.
And God is good all the time, so we live a life of praise and keeping promises.