For post second temple Jews, sincere repentance is equivalent to the rebuilding of the Temple, the restoration of the altar, and the offering of all the sacrifices. Genuine repentance is manifested when the same temptation to sin, under the same conditions, is ever after resolutely resisted. Interpreting Solomon, the Rabbis came to the conclusion that a man who confesses his sin but still clings to a defiled thing, though he bathes, he will not be clean...but if he casts the defiling thing away even one single bath will cleanse him (based upon Proverbs 28:13).
Most Jews and Christians agree that repentance is required before atonement. Though man ought to be penitent every day, according to the Rabbis, the first ten days of every year are the acceptable time announced by the prophet (Isaiah 55:6): "Seek the Lord while he may be found, call upon him while he is near. According to the Talmud, repentance and the Day of Atonement only absolve one from sins committed against God; from sins against another person they absolve only when restitution has been made and the pardon of the offended party has been obtained.
Every penitent sinner is graciously received by God. (Jeremiah 31:9). Jewish doctrine holds that it is never too late, even on the day of death, to return to God with sincere repentance for "as the sea is always open for every one who wishes to cleanse himself, the Gates of Repentance (Hovot ha-Levavot) are always open to the sinner" Jewish doctrine states that the hand of God is continually stretched out to receive a sinner. Talmud Berakhoth even puts forth the rather bold assertion that a repentant sinner attains a more exalted spiritual eminence than one who has never sinned and that it is a sin to taunt a repentant sinner by recalling their former sinful ways.
Growing up as an Evangelical, the word repentance scared the hell out of me. It meant "don't do that again or else...you'll have to repent again." To me that appeared to be an impossible undertaking. I knew I was going to tell another lie or even worse, use another curse word or some other such horrible deed that was sure to lead right to heroin addiction and eventually murder as far as church leaders saw it.
John Calvin said that repentance may be justly defined to be a true conversion of our life to God, proceeding from a serious fear of God, and consisting in the mortification of the flesh and of the old man, and in the vivification of the Spirit.
