A vicar preached on the Baptism of our Lord, relating the planting of the flag on Iwo Jima during WWII to baptism. The flag was planted on the highest point of the island only four days into the battle. But the battle would go on for a month before the island was secured.
In baptism, God planted the flag of the Holy Spirit in our rocky hearts claiming us as his own. However, being baptized into Christ does not mean the battle is over. The Old Evil Foe still wages war, holes up in a cavity of our life which we withhold when confessing our sins, or some protected area where we refuse to allow the Holy Spirit to lead us into a new way of living.
Jesus himself is an example of that struggle. Though baptized, blessed by the father and equipped with the Spirit, he was immediately thrust into the wilderness where for forty days he was tempted by Satan.
In the wilderness, God sent his angels to minister to him. These were the heavenly host who sang “Glory!” at Jesus birth. God gives his own heavenly host to minster to us in the battle for our hearts where he has planted his flag in our baptism.