Jesus is the Son of God
We can make the mistake in thinking that once the Holy Spirit descended upon the Apostles, all conflicts in the Church were immediately worked out. That was, of course, true for the Trinity, but it did take a little time for the Church to discern some things. That Jesus was the divine Son of God was one of these areas. Thanks be to God for the tireless and courageous witness of Saint Athanasius the saint we celebrate today, who at great risk to himself defended this truth.