This chapter repeats what we read in 2 Samuel 7. David wants to build God a house, but God says no. God also says he will establish David’s house forever. This promise is fulfilled in Jesus who is David’s descendant and will truly reign forever.
Not being able to build a house for God must have been a disappointment to David, yet still he praises God for the promises he has made. Even when we go through disappointment, we can rejoice in his promises.