“O LORD, in your strength, the King rejoices …”
If this is a prophetic look at Christ, our King, then what we are being told here is that the King, the Son of God, rejoices in the LORD, the Father. God the Son rejoices in the Father. God rejoices in Himself. And so He should. The more crass among us, and the charge has also been made by many unbelievers of one variety or another, will argue that for God to rejoice in Himself is for God to be the biggest egomaniac there can possibly be. Where is the humility? Where is the valuing of others above oneself? And that is the problem. How can God value anything above Himself when He is the most valuable thing there can be? If God the Son rejoices in anything more than He rejoices in the Father then He is guilty of idolatry. God cannot rejoice in anything more than He rejoices in Himself because He is the greatest worship worthy Being there is. How can God love something better then Himself? There is nothing better than He is.
It is glory for the Father that is the reason for the Son creating the universe (Psalm 19:1). It is for God’s glory that the Son comes to save people (John 17:1-3). Jesus always is working for the praise of the glory of His Father. The Holy Spirit works for the glory of the Son (John 16:14). The Father calls us to glorify the Son (Colossians 1:15-20). This is why we are brought to know Jesus Christ. This is why we are made in the first place. This is why we will live forever with Him. There is nothing that is not meant to point us to our great triune God for only He is worthy.
Before the angels said “peace on earth”. They said “glory to God in the highest”. It’s Christmas. I pray that you will be able to celebrate with true purpose – giving glory to the Father who sent the Son; giving glory to the Son who came; giving glory to the Spirit for His work of bringing you to Christ. Give glory to the one God who has done it all.