3:15 peace of God. See note on Philippians 4:7.
3:16 word of Christ. The “word of Christ”—at least for us today—can only be the Holy Scriptures, so this is an exhortation to memorize Scripture. See also Psalm 119:11. Note that Christ and the apostles frequently quoted from memory appropriate Scriptures, sometimes lengthy passages, in their discourses and sermons. This is the only occurrence of the phrase “word of Christ.”
3:16 admonishing one another. This exhortation is not referring to public worship, but to daily conversation and even to solitary activity—“talking to yourselves” and “making melody in your heart to the Lord” (Ephesians 5:19).
3:16 psalms. “Psalms” clearly refers specifically to the psalms in the Old Testament, which were commonly sung both by the pre-Christian Jews and by the early church, as well as in many churches ever since. Note also Ephesians 5:19.
3:16 hymns. “Hymns” is descriptive of songs similar in content and motivation to the psalms, but not taken from the divinely inspired psalms of the Old Testament.
3:16 spiritual songs. “Spiritual songs” refers to songs with a Biblical theme but with a more popular style tune than the others. The Greek for “song” is ode, which is a generic term for any kind of song. The adjective “spiritual,” however, delimits it to songs with Christian content.