In verse 7b David gives his vow of praise — a distinctive of this type of Psalm. In distress he trusts God for release; in release he promises to praise God for his deliverance. He asks God to bring him out from his prison-like box in order that he might be able to give public acknowledgement to the name of God. Here we see again what many Psalms display: Praise is public and vocal and comes as a response to the person and actions of God. David longs for a day in which he will be able to praise God in the presence of the community. Prayer is the rootage, and praise is the flower. We pray for God’s aid; we praise Him for who He is and for what He does on our behalf.
Psalm 142 concludes on a lovely note of assurance that God has heard. He will deliver, and He will magnify His great name. David sings:
The righteous will encrown me,
For You will have done bountifully with me! (v.7 cd)
– And I Will Praise Him: A Guide to Worship in the Psalms, Ronald B. Allen