All the commands of the New Testament to the “new man” in Christ are in the “imperative mood."
They are, after all, commands.
But it is extremely helpful for the believer to think of them as “indicative mood” (declarative statements) — each one a faithful description of who I NOW AM, because I am a “new creature” IN CHRIST.
Paul describes the new man as “created after God (according to God’s likeness) in righteousness and true holiness” (Ephesians 4:24).
In brief, the commands addressed to the new man in Christ are the practical outworking, or living out, of this righteous LIFE in us.
In other words, each command is God saying, “Beloved, this is what that “righteousness and true holiness” LOOKS LIKE in practical living . . .
THIS . . . IS WHO YOU ARE."
When we were born again (John 3:3), the Bible says we DIED WITH CHRIST to the “old man,” the world, the flesh, and the Law (Romans 6:1-8:14; Galatians 1:4; 2:16, 20; 5:24; 6:14). We have been set free from the Law (Romans 7:6).
As new creatures, we have actually not been given another Law to live under, BUT A LIFE TO LIVE IN (though James does refer to it as “the perfect law OF LIBERTY”).
This righteous LIFE is vividly "described" by every command and exhortation given to the believer; the new man in Christ (II Corinthians 5:17).
So, when Paul tells me to “put on the new man,” he is telling me to agree, by faith, that I AM that individual described or pictured in these commands.
I am to take God at His Word and BELIEVE THAT.
Then, every command becomes a PROMISE of what Christ can and will live out in me as I trust Him to do so.
It is called “the Law of Liberty,” because these Grace-commands of God SET ME FREE to live as the new man I truly now am.