Jesus said that the missionary enterprise, preaching repentance and faith to all nations, was written already in the Old Testament.
Luke 24:44-53New International Version (NIV)
44 He said to them, “This is what I told you while I was still with you: Everything must be fulfilled that is written about me in the Law of Moses, the Prophets and the Psalms.”
45 Then he opened their minds so they could understand the Scriptures. 46 He told them, “This is what is written: The Messiah will suffer and rise from the dead on the third day, 47 and repentance for the forgiveness of sins will be preached in his name to all nations, beginning at Jerusalem.
Repentance and faith are pictured so well in Psalm 51. David’s pleas that God create in him a clean heart is a picture of sorrow over sin and faith that God is the God who “blots out transgression”. We used to sing that Psalm in the offertory every Sunday and it is still a part of the liturgy that most of us memorized.
This is my take on the offertory and a song I wrote called “Merciful Maker of All Things”.