The author ends this series of Old Testament quotes by citing Psalm 110:1. This verse celebrates Christ's exaltation (see also study notes on Luke 20:42–43; 22:69; 1 Corinthians 15:25; Ephesians 1:19–22).
The image of the Son's enemies as a footstool under his feet shows their complete defeat (see Hebrews 2:8). In ancient times, a victorious king would place his foot on an enemy's neck or back as a sign of control.