Summary: Depression sometimes hits us, but we often don't know how to handle it or get out of it. In fact, we feel guilty for even being depressed. But these psalms give us some clues on what to do when we are down.
The book of Psalms is actually made up of four books. Psalm 41 (quickview)  ends Book One, which is made up almost entirely of David’s psalms. The final psalms of each book are similar in that they offer a doxology of praise to God. As such they are called “seam” psalms because they piece the four books together as one. In this psalm David is suffering illness, such as we saw in Psalm 38 (quickview) , but sin isn’t the primary cause. Here, David is more worried that those that hate him and his love for Yahweh will feel triumphant if he dies.
1 – 3
David characterizes the person of loves Yahweh as one who “cares” for the poor—those who are suffering economically. This doesn’t mean that by doing acts of charity God will “owe” you and bless you. It is simply the natural result of someone who loves God. God says over and over in His Word that we should look out for those who are victims and without strength.
There are seven promises given in these three verses—things that God will do for those who exhibit His character:
Save in time of adversity. “Adversity” is simply the word “bad”. When bad things happen to people who love God, the Lord gives them “slipperiness.” That’s what “save” means here. In short, God will not allow anything to happen to you that is not in His will and will not further His kingdom. It does not mean you won’t experience adversity, but God is the one in ultimate control.
Keep and preserve. Keep means “to put a hedge around.” You are under God’s protection and preservation even in the midst of trouble. “Preserve” literally means “to live.” God will keep you alive without fail until the moment He wants to take you to be with Him.
“Not deliver him” no matter what bad things the world, the flesh, and the devil mean to do to you, God will not allow any of them to prosper. The enemy’s javelins become God’s spear.
“Sustain” means to support. Though the Hebrew of verse 3 is a little difficult, you could say that when we are ill, God becomes our nurse and nurses us back to full health.
With these promises you can march out in full confidence that nothing that is thrown up against you in this life can stop you from loving and serving God!
4 – 9
David seems to have this constant problem, that those that dislike him want him either disgraced for killed. If there was a sin involved in this situation, it appears to have been confessed or wasn’t a real sin (because in verse 12 he speaks of his integrity). When the enemy lacks a real case against us, he just lies, which is what he is good at. They really thought David was going to die and they couldn’t wait.
10 – 12
David asks God to lift him up from his sickbed and thus show his enemies that they have not triumphed. All David wants is to be in God’s presence—to not be separated from His God. And that should be our desire too—that no matter what befalls us, we will triumph because Jesus triumphed and promised we would be with Him forever.