Referring to the glorious angels, Trapp remarks that they do the will of God,

1. Cheerfully; whence they are said to have wings, six wings a-piece, Isa 6:2.
2. Humbly; therefore with two they cover their faces.
3. Faithfully, without partiality; with two they covered or harnessed their feet.
4. Speedily and zealously; with two they fly abroad the world upon God’s errand, and for the good of them that shall be saved, Heb 1:14, burning and being all on a light fire, with infinite love to God and his saints, their fellow servants, Rev 22:9, whence they are called seraphims or burning creatures.
5. Constantly: Jacob saw them ascending, to contemplate and praise God, and to minister unto him, Dan 7:10. He saw them also descending, to dispense God’s benefits and to execute his judgments, Rev 15:6.