Sure Mercy?

I did some reading Sunday afternoon--trying to keep the sabbath holy and all.  I was reading in Acts 13 and came across a phrase I hadn't ever noticed before.  It really struck me.  It was about the "sure mercies of  David".  I didn't know what that was.  The footnote sent me to Isaiah.  That figures.  No wonder I didn't get it.  Anyway,  apparently,  David was promised resurrection.  I know that everyone on earth gets the free gift of resurrection, but this reading really made me think.

I have thought a lot about David over the past year.  He writes so much about his sorrow and remorse and begs forgiveness of God through so many of the Psalms.  He sounds so broken.  He didn't actually kill Bathsheba's husband--but he did cause his death.   (Yes,  I'm still waiting for God to tell me my yelling at and demanding too much of Ian wasn't the cause of  his death.)

If David was responsible for an innocent man's life,  would the promise of resurrection feel like mercy?  Would you really want to be resurrected if you knew that meant that you would then have to live eternally with what you had done?  It seems to me not being resurrected would be the more merciful choice.    I obviously have a whole lot to learn.