Faith should later again flow forth from our heart’s depths to our neighbor freely and unhindered in good works; not that we wish to rest our salvation in them; for God will not have that, but wishes the conscience to rest in himself alone.
There are plenty of reasons why you do not already do whatever you want out of fear of the law, and you will find these reasons persist and remain long after the gospel has its way with you.
Pentecost reminds us of not only what happened on that day described in Acts 2 but what is happening every day: the Spirit of God working in and through God’s people, according to his word.