Except a man be born again, he cannot see the kingdom of God

Bible, John iii, 3
For Buddhists born again means reborn (reincarnation), and it's all about the Karma and the correlation between cause and effect, "the law of causality". Nothing is about coincidence, it is not about luck, it is about destiny, as you sow, so shall you reap, that is the law of nature. Each person has a different personality, different thoughts and different experiences in each life (reincarnation), for this reason every person has a different destiny, and we can see how fair is the heaven. Yet there are different social classes, rich and poor, healthy and sick, good and bad, but how could this happen? The answer is "because of our Karma", we have received more than we have given, and if we understand how important is the relation between Karma and our lifes, surely we will not damage ourselves and we will select carefully the good seeds from the bad ones, but this is not enough, we also have to return the favors, pay our debts, and repent for everything bad we've done; and start to do good things to create merits and virtues to eliminate the bad Karma and fill the soul with new Karma.