17But thanks be to God that though you were slaves of sin, you became obedient from the heart to that form of teaching to which you were committed, 18and having been freed from sin, you became slaves of righteousness.
That form of teaching to which you were committed
The word “form” here translates the Greek word tupos which is where we get the English word “type”. The picture that it conveys is a sort of stamp that would be set on something and then struck to make the same impression every time. This form of teaching to which we were committed is the teaching of salvation by Grace through faith. As we have seen already in Romans 6:1-14, that Grace is not just our “get out of Hell free” card, it is to be our operating principle of existence for all things thereafter. We began in faith in what Christ has done in the cross, we continue in faith in what God did in resurrecting Him from the dead. At the end of all things we will see that everything that was good or worthwhile in our lives was what we allowed Him to do in and through us, and anytime we tried to get in the way we goofed everything up.