Nehemiah 9:6
6
Thou, even thou, art LORD alone; thou hast made heaven, the heaven of heavens, with all their host, the earth, and all things that are therein, the seas, and all that is therein, and thou preservest them all; and the host of heaven worshippeth thee.
Voluntary
In Ezekiel 46:12, this signifies something that is done from love to the Lord and the neighbor. (True Christian Religion 580)