This psalm gives us words to express those times when we are in need--times when we cried aloud to God, but didn't get the help we needed when we wanted or expected it, those times when God didn't act or we didn't recognize God's act as something that was needed for our plight:
....my soul refused to be comforted....
Verses 9-10, that are omitted in this week's reading, reminds us what God has already done. Yet, this reminder carries a tone of resentment--God has done so much for so many, what reason does God have for not helping me right now?
The tone changes in verse 11. The psalmist turns from talking about God to talking to God,
I will remember your wonders of old when the waters saw you, the very deep trembled.
I'm suggesting that we take the reference to waters as literal--the memory of the rescue of the people led by Moses as they escaping through the river from slavery in Egypt--or as a metaphor for any time that the situation seems as hopeless as facing a river with an army coming right at us.
Elijah was threatened by the powerful of his community and his time. The psalmist was facing a threat in his own time. We don't know exactly what it was or if we even have to read it as a situation in David's life--but it could be. And God's people continue to suffer threats in their time--in our own time.
This psalm allows us to say in words that when we face a troubling, scary situation, one in which we feel controlled by forces that no human being could possibly handle alone, then we turn for help to the One who has protected them and us before.
The Jewish Study Bible commentary suggests that we also look at Isaiah 51:9-1-; Psalms 18:8-16; 114:3-6