David encourages us to worship and give praise to God as he did in the psalms. David knew all about this seeing how he was a psalmist, or worship leader. He experienced the closeness to God as he worshipped Him through song.We have felt that same closeness and joy when we sing to the Lord. For example the song "Blessed be Your name" always makes me feel like Jesus is right there listening to me; i always feel so close to God with that song! And there are so many worshipful songs out there that draw us so close to Jesus. And Jesus wants us to be close to Him, He wants us to be happy and rejoice in Him. Thats why David says sing to the Lord. As we are called to preach the word in season and out of season(2tim4:2), i believe the same applies to worship. So as David says to praise Him in song, lets continue to do it and draw closer and closer to Jesus.