Walls of Jericho
Joshua 6: 20: "So the people shouted when they blew with the trumpets: and it came to pass, when the people heard the sound of the trumpet, and the people shouted with a great shout, that the wall fell down flat, so that the people went up into the city, every man straight before him, and they took the city."
II Timothy 2: 4: "No man that warreth entangleth himself with the affairs of this life; that he may please him who hath chosen him to be a soldier."
Hebrews 11: 30: "By faith the walls of Jericho fell down, after they were compassed about seven days."
"A ship in harbor is safe, but that is not what ships are built for."