'Joyfully' in the Bible

David told the leaders of the Levites to appoint some of their relatives as musicians; they were to play various instruments, including stringed instruments and cymbals, and to sing loudly and joyfully.

I know, my God, that You test the heart and that You are pleased with what is right. I have willingly given all these things with an upright heart, and now I have seen Your people who are present here giving joyfully and willingly to You.