1 Samuel - Chapter 5

The Philistines have defeated the Israelites in battle, and they have taken the ark of the covenant back to their stronghold at Ashdod.

After the Philistines had captured the ark of God, they took it from Ebenezer to Ashdod. Then they carried the ark into Dagon’s temple and set it beside Dagon. When the people of Ashdod rose early the next day, there was Dagon, fallen on his face on the ground before the ark of the Lord! They took Dagon and put him back in his place. But the following morning when they rose, there was Dagon, fallen on his face on the ground before the ark of the Lord! His head and hands had been broken off and were lying on the threshold; only his body remained.

The battle between the one true God and the idol Dagon is a demonstration of God's power.  There could be a link to Jesus in the description of the idol Dagon.  It is generally described as being half man and half fish - a kind of merman.  When Jesus called his disciples he included four fishermen, and he performed miraculous catches of fish - as in 1 Samuel 5 God had power over the idol Dagon, Jesus had power over the fish of the sea.