This psalm is built around one request at its heart. Petitions for help open it, praise of God's incomparable greatness fills the middle, and petitions return near the end, so that urgent need is wrapped around a confession of who God is, the way a person wraps both hands around something he means to hold. At the center sits one line, and every other verse leans toward it: 11"Teach me your way, O LORD, that I may walk in your truth."
David opens in plain need. 1"I am poor and needy." Then something unusual: he describes God before he describes his trouble. 5"you, O Lord, are good and forgiving, abounding in steadfast love to all who call upon you." The psalm is more occupied with telling God about God than with telling God about David's crisis. It states the character of the one addressed, renews David's commitment, and only near the end names the actual danger. Prayer modeled this way does not rush to the request. It grounds the request in who is being asked.
The middle widens the lens as far as it will go. 8"There is none like you among the gods, O Lord." 9"All the nations you have made shall come and worship before you." 10"you alone are God." Every rival claim any nation made for its own gods collapses beside this one. It is here, surrounded by declarations of God's greatness, that David asks for what the whole psalm is built to carry. The image behind "way" is an actual road, instruction in how to walk and more than a list of what to believe.
Then the second half of the verse: 11"unite my heart to fear your name." The plea is to be delivered from a divided heart, two-faced even with God, and to be given one steady aim that does not bend under threat or reward. A heart becomes single by fixing on something outside itself that is worth the whole of its attention. The lines of an undivided heart meet at a point beyond the one praying, in the fear of the LORD.
The unity David asks for shows up at once in how he responds. 12"I give thanks to you, O Lord my God, with my whole heart." Thanks with the whole heart matches the wholeness just requested. 13"you have delivered my soul from the depths of Sheol." An undivided heart is renewed again and again, sometimes on the far side of falling.
Near the end the danger surfaces, framed by the same description of God that opened the psalm. 15"a God merciful and gracious, slow to anger and abounding in steadfast love and faithfulness." The sentence comes from God's self-description to Moses after the golden calf (Exodus 34:6), repeated across the Old Testament until it works like a creed, the line Israel returned to whenever mercy was the thing most needed. David grounds his urgent request in what God has already shown himself to be, and in nothing he has done to deserve an answer.
The closing request is the opening one, help for the poor and needy, but now it rests on a foundation the middle of the psalm took time to build. Ask for the same thing today. Ask first for who God is, and then for what you need.
Prayer
Father, you are good and forgiving, merciful and gracious, slow to anger and abounding in steadfast love, as you told Moses and have proved ever since. Teach us your way, that we may walk in your truth, and unite our divided hearts to fear your name. Whatever depths you have delivered our souls from, let our thanksgiving match it, with a whole heart. In Jesus' name, amen.