The Messenger of Allah ﷺ said, "Tawba from a sin is to repent from it and never return to it."
حدثنا عبد الله قال قرأت على أبي حدثنا علي بن عاصم قال أخبرنا الهجري عن أبي الأحوص
قال رسول الله ﷺ التوبة من الذنب أن يتوب منه ثم لا يعود فيه
No references are available.
Its isnad is daif, due to the weakness of Hajari. It is found in Majma al-Zawaid 10:199–200, where it says, Ahmad narrated it, and its isnad is daif. Suyuti mentioned it in Jami Saghir 3413 with the same meaning, attributing it to Ibn Mardawayh and Bayhaqi in Shuab, and he marked it with the sign of daif.