The psalmist is crying out for deliverance from his persecutors. He wants to be delivered so he can continue a life of Torah observance. He cries out to God all night long — and the foundation for his cry for deliverance is significant:
In your steadfast love hear my voice;
O LORD, in your justice preserve my life (149).
It is often said that theology (what we think of God) should shape our prayers; it sure does this psalmist. In fact, it has been said that our theology determines our prayer and our prayer reveals our theology.

The psalmist thinks God should deliver him because:
1. Of God’s steadfast love and
2. Of God’s own justice.
God’s chesed and God’s mishpat. The theology of the psalmist is this: God is faithful in his love and God’s faithful love should give rise to God’s judgment on behalf of the psalmist.
What we see here is the confidence of the psalmist in God.