The Gospel Coalition 2017 National Conference was an outstanding time of teaching and worship. The plenary sessions worked through the book of Galatians and celebrated the 500th anniversary of the Protestant Reformation. The main sessions are now available online here.
If you only have time to watch three, might I suggest the following:
“Paul’s Pilgrimage, Paul’s Plea: Galatians 1” by John Piper
“On John Calvin” by Kevin DeYoung
“Gospel Freedom, Gospel Fruit: Galatians 5” by Thabiti Anyabwile