2 Corinthians
King James Version (KJV)

“For the love of Christ constraineth us; because we thus judge, that if one died for all, then were all dead:”
King James Version (KJV)
5:14 For the love of Christ - To us, and our love to him. Constraineth us - Both to the one and the other; beareth us on with such a strong, steady, prevailing influence, as winds and tides exert when they waft the vessel to its destined harbour. While we thus judge, that if Christ died for all, then are all, even the best of men, naturally dead - In a state of spiritual death, and liable to death eternal. For had any man been otherwise, Christ had not needed to have died for him.
2Co 5:14 For the love of Christ constraineth us. It was the power that moved him in all his conduct. If one died for all, then were all dead. I thus judge that if Christ died for all, all in Christ have died with him to a life of sin. Baptized into his death we must be dead to sin. The next verse shows that this is the meaning. Compare Ro 6:3,4,6,11 Ga 5:4.