'Sing to the Lord' in the Bible

When he had consulted with the people, he appointed those who sang to the Lord and those who praised Him in their holy (priestly) attire, as they went out before the army and said, “Praise and give thanks to the Lord, for His mercy and lovingkindness endure forever.”

On the fourth day they all came together in the Valley of Blessing, and there they gave blessing to the Lord; for which cause that place has been named the Valley of Blessing to this day.

Hezekiah ordered the burnt sacrifice to be offered on the altar. As they began to offer the sacrifice, they also began to sing to the Lord, accompanied by the trumpets and the musical instruments of King David of Israel.