Psalms 21:1

Protection, susceptione. Hebrew ayeleth, hathuchar, or "for a speedy interposition," or succour. See ver. 2, 20, and 25.

St. Jerome, "the morning stag." (Haydock)

Many of the titles are almost inexplicable, and this is one of the most puzzling; (Calmet) but is of no service for understanding the psalm, which certainly speaks of Jesus Christ, as the apostles have quoted several texts, and Theodorus of Mopsuesta was condemned for asserting that it was only accommodated to him. (Conc. v. col. 4.) (Berthier)

Grotius comes too near this system, by explaining it of Christ only in a figurative sense. We ought to do quite the reverse, if we allow that some verses regard David, as a figure of the Messias; (Calmet) or rather, as the same person speaks throughout, we must understand the whole of Him. (Berthier, t. ii.)

The Jews were formerly of the same opinion, (Lyranus) but seeing the use which was made of this psalm by Christians, they have explained it of David, or of the miseries of the nation. Septuagint seem to intimate that this psalm was sung at the morning service, (Calmet) or referred to the coming, or resurrection of our Saviour, (St. Augustine; Worthington; Psalm iii. 6.; Menochius) after the long night of infidelity. (Didymus)

He is represented as the hart, or beautiful hind, whom the Jews hunted unto death, ver. 17. Some band of musicians might be styled, after "the morning hind," as another seems to be after "the mute dove;" (Psalm lv.) and the wine presses, or "band of Geth;" (Psalm viii., &c.) though we cannot pretend to give a reason for these titles. Many, who are unwilling to confess their ignorance, say that these terms allude to some musical instrument, or favourite song, &c. (Calmet)