In this psalm, David is praising God for rescue from death in the past (verses 1-5), asking God for rescue now (verses 8-10), and thanking Him that rescue is coming (verses 11-12).
We can praise God for rescue in the past. He has healed you (v2). He has rescued you from eternal death (v3) because He brought Jesus out of the grave. Nothing is too hard for Him.
Just as the Lord has helped you in the past, you can ask Him to help you now (v8-10). Some of you are still not 100% well. Tell Him. Remind Him that nothing is too hard for Him. He rose and conquered the grave.
But there are two important lessons from this psalm.
First, do we trust ourselves or Him? In v6 and 7, David looks back to when he was self-confident. All the things that have happened show us that we need HIM.
Second, the psalm ends with praise, even before the answer has come (v11-12). He has already redeemed you, He has saved you from eternal death. Even if trouble is hard now, let’s praise Him for all He has done and for what He will do.