Above it stood, as ministers attending upon their Lord, and waiting to receive and execute his commands, the seraphims; certain holy and blessed angels, thus called from fire and burning, which this word properly signifies; to represent either,
1. Their nature, which is bright and glorious, subtile, and pure, and spiritual, like fire; or,
2. Their property, of fervent zeal for God's service and glory; or,
3. Their office and present employment, which was to execute God's vengeance upon the Jews, and to burn them up like dross. Covered his face, out of profound reverence, as being so sensible of the infinite distance between God and him, that he durst not presume to look directly upon him, and judged himself neither able nor worthy to behold the brightness of his glory. Covered his feet; either,
1. His secret parts, which sometimes come under that name, as Deuteronomy 28:57 Isaiah 7:20, Isaiah 36:12; of which see more in my Latin Synopsis upon Exodus 4:25. And so this is done for our instruction, to teach us modesty and chastity. Or,
2. Their feet properly so called, as that word is generally used; from which use we should not depart without necessity, which, with submission, seems not to be in this place. And so this may signify a sense of their own natural, though not moral infirmity, and a desire that God would not too severely examine all their ways and actions, which the feet commonly signify, because though they did not swerve from God's commands, yet they were not worthy of the acceptation, nor suitable to the dignity of so glorious a Majesty. Did fly; which signifies their great forwardness and expedition in executing God's commands. Compare Daniel 9:21.