Repentance (/tʃuvɑː/; Hebrew: תשובה, romanized: tǝšūvā "return") is one element of atoning for sin in Judaism.
In such a case, Rabbi Nosson Scherman recommends devising "a personal system of reward and punishment" and avoiding circumstances that may cause temptation toward the relevant sin.
[7] One is shown to have fully repented if they are presented with an opportunity to perform the same sin under the same conditions, yet they manage to refrain from doing so.
A parable is told in the Talmud that Rabbi Eliezer taught his disciples, "Repent one day before your death."
The disciples politely questioned whether one can know the day of one's death, so Rabbi Eliezer answered, "All the more reason, therefore, to repent today, lest one die tomorrow.
"[10] Now on the day of Rosh Hashana, the beginning of the 10 days of repentance - this is a very holy hour and auspicious time to create a pleasant delight before the Creator to want to cry tears of joys…Because of Judaism's understanding of the annual process of Divine Judgment, Jews believe that God is especially open to repentance during the period from the beginning of the month of Elul through the Ten Days of Repentance (including Rosh HaShanah and Yom Kippur), and, according to Kabbalah, Hoshana Rabbah.
[1] Another occasion on which forgiveness is granted is whenever the entire community gathers and cries out to God full-heartedly due to their distress.
According to Joseph Dov Soloveitchik, the meaning is that a person who repents out of love embarks on a journey of self-transformation, in which they use the pain of their failure as a spur to self-improvement.
(Although texts mention some specific categories for whom the way back will be exceedingly hard, such as the slanderer, the habitual gossiper, and the malicious person.)