Psalms - Chapter 116
David says that he loves G-d because G-d always hears his prayers. No matter how bad things got, even when death seemed imminent, David would call out to G-d for help. G-d is gracious, He is righteous and He is merciful. He protects simple people, who do not have the ability to make plans to save themselves. David was brought low, but G-d saved him from his troubles.
David tells his own soul to relax, now that G-d has treated him with kindness. He saved David from death, from tears, and from falling into traps set for him by his enemies. David walks before G-d in the land of the living. (Rashi says this means Israel, where the "living G-d" is worshiped, as opposed to the "dead" idols of foreign lands.) David never lost his faith in G-d, no matter how much he suffered. He did, however, let himself be discouraged into thinking that all people are deceitful, a position he later reconsidered. (This may refer to the incident in which David was tricked into thinking that his faithful friend Mephiboshes had betrayed him, which he later found out was not the case. See events at the end of II Samuel.)
David asks how he can possibly repay G-d for all He has done for him. He raises the cup of salvation and calls out in G-d's Name. He will bring the sacrifices of thanks that he has promised, in full view of the nation.
The death of His righteous is metaphorically "difficult" for G-d and not something He undertakes lightly. David asks G-d for a favor (possibly to merit to see the Messianic era) since he is a faithful servant, descended from Ruth, who embraced G-d. G-d relaxed the prohibition against Moabite marriage long enough to allow for the circumstances leading to David's birth to come about. David will publicly praise and thank G-d.
Like the previous Psalm, this one is divided into two portions in Hallel, Ahavti (omitted in "half Hallel") and Mah Ashiv Lashem (always recited).