George Leo Haydock, on Ps 18:1

“Unto the end. A psalm for David.”

“David. It is not known when this was composed. David praises the works and law of God. Some passages are applied to Jesus Christ and his apostles, Romans x. 18. (Calmet) — When any text of a psalm is thus quoted, many judiciously conclude that the whole must be understood in the same sense, as the harmony will thus be greater. It seems there are two literal senses here, one regarding the law, whether natural or Mosaic; the other pertaining to the apostles and the law of the gospel; (Berthier) the “beloved” David of the latter days. (Worthington)”

Imported from an open dataset — not yet checked against the printed edition.