There is no person so dear to a Christian as the Lord Jesus Christ. It is therefore no surprise to find a song of worship in the New Testament focussed entirely on the perfections and accomplishments of Jesus.
In Colossians 1:13-14 the Apostle Paul elaborates on the saving work of God the Father. As it to be expected, the Father’s beloved Son is mentioned as the One through Whom our sins are forgiven. If you would then skip verses 15 to 20, and pick it up again in verse 21, you’ll find the elaboration on salvation continuing as though there was no interruption.
Yet, verses 15 to 20 are there. And need to be explained. There is no other explanation than that Paul was so overcome by Christ’s glory, that He erupted in what is no doubt a New Testament song. Like the Psalms of the Old Testament it is packed with truth about God, but in terms of the New Testament revelation.
Read it as slowly as it would perhaps have been sung. Meditate on each line. May it inform your own affections for the Lord.