The readings for the first Sunday in Advent are from Isaiah 2:1-5; Romans 13:8-14; and Matthew 21:1-11 (Palm Sunday) or 24:36-44.
Isaiah foretells the coming of the mountain of the Lord’s house, which is the Son of God, born true man of the virgin Mary. His coming brings peace (swords beaten to make plows). Such good promises urge us to come and walk in the light of the Lord.
Paul’s letter to the Romans instructs us in the conduct of those who are coming through the course of this world, walking in the light of the Lord and watching for His coming. The way to walk and watch is to keep putting on the Lord Jesus, which equips us to pursue love of neighbor.
Matthew records Jesus (the mountain of the Lord’s house) coming to Mount Zion on Palm Sunday. He came just as surely as the prophets predicted (Zech 9). Just as surely as the floods came once Noah had finished the ark, so Jesus will return to claim all of us who wait, watch, and hope in the ark of the Christian church.