Commentaries:
Paul was speaking to those Jews who were not yet converted. At least, we hope that they were not yet converted and that they had opportunity yet to repent of those things. But this makes it very plain that God's name is hallowed—or profaned—by our conduct. The third commandment is kept—or broken—by the same. This is the commandment that tests the quality of our witness.
John W. Ritenbaugh
Holiness (Part 1)
By our conduct, we hallow or profane God's name. We keep or break the third commandment the same way. This commandment sets the standard for our witness and tests its quality. God's name is the standard. If we take the name of God and use it in any way that denies its true meaning and God's character, we are either breaking this commandment or are on the way to doing so.
People can judge and accuse, saying, "This is God's church, and they do such things? If this is the true church, why doesn't God do something about it?" He is patient and longsuffering, and He will do something about it. He will save His people for His name's sake, but it will hurt.
John W. Ritenbaugh
The Third Commandment
Other Forerunner Commentary entries containing Romans 2:23:
John 14:6
Acts 17:11
James 1:22-25