This is a general principle that applies in life universally: Whatever a person submits to, he is that person’s (or thing’s) servant. (This same principle is referred to in 2 Peter 2:19b.)

The bond-slave is obligated to give absolute obedience to his sovereign. That master rules him. In this life we can choose one of two such masters, sin or righteousness.

Paul also hints here at the results: Sin’s service brings death; God’s service brings righteousness. But these ideas will be returned to for more emphasis.

The true Christians at Rome were those who “obeyed” (Greek: hearkened) from the heart the call of God in the gospel proclamation.

We pause here long enough to observe that one does not have the privilege, in life, to choose to have no master! He may think he does but will be inevitably deceived. Indeed, when one believes himself to be his own master, he is really the bond-slave of sin.

The truth is that every Christian has the new master and has broken with the old one. But it is also every Christian’s daily duty to serve that new master and refuse the old one.

The truth is, that a Christian does obey his new master in so far as the general habit and practice of his life are concerned (verse 18). But even the best of Christians is often tempted to hearken again to his old master and needs regular encouragement that he does not have to and must not.