Jn. 3:7 Marvel not that I said unto thee, Ye must be born again. We argue about HOW one is born again. Some believe in connection with baptism and others believe before faith and yet others at faith and some after faith. However, leaving all that to another thread. This thread deals with why new birth is a "must" or necessity and what exactly about man is born again. I believe the necessity of new birth is due to a "heart" problem in all fallen human beings. God looketh upon the heart because it is out of the heart all the issues of our our life originate. 1Sa 16:7 But the LORD said unto Samuel, Look not on his countenance, or on the height of his stature; because I have refused him: for the LORD seeth not as man seeth; for man looketh on the outward appearance, but the LORD looketh on the heart. Pr 4:23 Keep thy heart with all diligence; for out of it are the issues of life. The motive for all that we think, say and do has its source with our heart. As a man thinketh in his heart so is he, Solomon says. Mt. 15:18 But those things which proceed out of the mouth come forth from the heart; and they defile the man. 19 For out of the heart proceed evil thoughts, murders, adulteries, fornications, thefts, false witness, blasphemies: Salvation under the New covenant is described as God giving a new heart - Ezek. 36:26 or writing his Law upon the heart - 2 Cor. 3:3-6. IF this is true. Why do you suppose a man "must" be born again?