Help me, O Lord my God!
Save me according to your steadfast love!
Let them know that this is your hand;
you, O Lord, have done it!
Our great need for God to save us is so great that we should immediately rejoice when we call to Him for help. The psalmist is in deep need in this song. In the situation described here, enemies seek the destruction of his life. He calls out to God to save his soul from their schemes, even as he suffers under them. His enemy is described as wicked and deceitful (vs 2), hateful (vs 3), an oppressor of the poor (vs 16), and a cursing person (vs 17-18).
As the sinful attacks happen, the oppressed cries out to God for deliverance. He still suffers though. The one oppressed is poor and needy (vs 22), weak (vs 24), and scorned by others (vs 25). Giving himself to pray, he trusts in God to act rightly within His faithful love (vs4). The phrase "I give myself to prayer" literally reads "I am prayer". It is all he can do. He is powerless to do any other thing than beseech the Lord and trust that He will answer prayer.
And when I am in deep need, I should be a man of prayer. My life should be a prayer. I need not be afraid when I am prayer, for God will hear. God will provide. God will protect His children and judge those who wickedly work against Him. In faith, when we suffer under other people, we must "be" prayer.