Old Testament readings use the Septuagint , the Scripture the apostles quoted. Masoretic numbering shown for reference.Learn why
LXX2012

Psalms 56:1

(57) For the end. Destroy not: by David, for a memorial, when he fled from the presence of Saul to the cave. Have mercy, upon me, O God, have mercy upon me: for my soul has trusted in you: and in the shadow of your wings will I hope, until the iniquity have passed away.

Read in other translations