Repentance as we know it today is not a biblical concept despite the thinking of many that the prophet Hosea talked about it. Hosea 14:2 states “Shuva Yisrael ad Hashem Elokekha,” “Return Israel to the Lord your God.” Actually, Hosea says in chapter 14 what he said several times in earlier chapters: stop worshiping idols and worship only God. It was only long after the lifetime of Hosea that Judaism developed the idea that one can repair wrongs that one committed by repentance.
Neither the term teshuva nor the concept of repentance as we know it today appear in the Torah. The ancients, Israelites and non-Israelites, believed that what one said, especially vows, or what one did cannot be erased. When an egg is broken, its shards cannot be reassembled. Misdeeds, they thought, are remedied only by punishment.
Scholars, as I explained in my earlier books, suppose that the current idea that people can nullify misdeeds by doing teshuva developed in three stages. It began around 722 BCE. I wrote about the history of repentance in my earlier books and will not will not reiterate the history here. Instead, I will show that the current Jewish concept that one can repair wrongs by repentance, does not exist in Christianity.
The post-Hosea concept of repentance, teshuva in Hebrew, dealing with common behavior not idol worship is a practical endeavor. Repentance doesn’t magically absolve people of wrongs they committed. It’s not abracadabra. Jewish repentance practices such as saying prayers and giving charity are designed to remind people to take practical measures to correct their behavior. It is a mistake to believe that Jews go to the synagogue during Rosh Hashanah and Yom Kippur and say prayers because many of these prayers will cause God to wipe out the wrongs we committed. Prayers do not do this. The purpose of the prayers is to prompt us to correct the wrongs we did in the past and change our future behavior. It is we who do the change.
Most people misunderstand repentance and confessions as they do sacrifices, as pseudo-magical recitations that remove misdeeds – as if words recited during a synagogue service could somehow change the past, erase the slap a husband gave his wife, and restore a loving relationship. “I don’t understand why you’re still angry,” the husband wails. “I did teshuva in the synagogue!” This isn’t the way life works.
Maimonides put it this way: teshuva is when a person decides to abandon his or her past misdeeds, resolves not to do them again, thinks how to correct them, and develops habits to assure they are not repeated. People do these four steps without the need of clergy, sacrifices, or even prayer.
Repentance requires the guilty person to act. It is not a state of mind, or words, or prayers, or the aid of another person. In the biblical book of Jonah, for example, it was not mind, words, prayers, or the aid of clerics, but the deeds of the people of Nineveh that caused God not to destroy their city as God had previously planned. “When God saw what they did, how they returned from their evil ways, God changed the evil that he had said he would do to them, and did not do it.”
The Christian idea is entirely different.
Christianity changed the concept to give Jesus a mission, specifically to explain why he was crucified. It happened this way. Paul felt he had a mission to convert pagans to Judaism, for the early Christians were Jews who had some attachment to Jesus. Paul taught the pagans that they could join the Jews without observing the Torah and such laws as circumcision and kosher, laws the pagans disliked and that held them back from converting. Paul said they can be “saved” by believing in Jesus, for Jesus died so that the wrongs that people did can be erased and they could be saved. If one denies Paul’s idea that the only way that one can erase past misdeeds is through belief in Jesus, this would be saying there was no reason for Jesus being crucified. Thus, while Jews continued to believe that they could erase their wrong deeds through repentance, Christianity began to believe that repentance could not nullify prior bad behaviors, only Jesus could do it for them, and one could approach Jesus through his clergy.
The biblical book “Song of Songs” about the love between a man and a woman was interpreted by Rabbi Akiva as an allegory describing the relationship between humans and God. Using this analogy, is it fair to say, the Christian idea seems to be: one spouse (God) says to the other spouse (humans), do nothing about the wrong you committed and do not talk to me about it, go instead to a mediator (clergy) and request the mediator to nullify what you did; I gave mediators the power to nullify your wrongs?
 Including apparently Babylonian Talmud, Yoma 86a.
 This concept is reflected in the Talmudic view that death atones. Babylonian Talmud, Shabbat 32a, Yoma 86a, Sanhedrin 43b and 47a–b.
 Olam Hatanakh, Devarim (Keter, 2002), 221–23.
 Mysteries of Judaism, Gefen Publishing House, 2014, and Unusual Bible Interpretations: Hosea, Gefen Publishing House, 2016.
 Mishneh Torah, Hilkhot Teshuva.
 There was no clear dogma in the early Christian era.