Halakhah sa Isaias 55:7: Mishneh Torah, Repentance, Sefer Chasidim & Sefer HaChinukh

What is repentance? The sinner shall cease sinning, and remove sin from his thoughts, and wholeheartedly conclude not to revert back to it, even as it is said: "Let the wicked forsake his way" (Is. 55.7); so, too, shall he be remorseful on what was past, even as it is said: "Surely after that I was turned, I repented" (Jer. 31. 19). In addition thereto he should take to witness Him Who knoweth all secrets that forever he will not turn to repeat that sin again, according to what it is said: "Say unto Him.… neither will we call any more the work of our hands our gods" (Hos. 14.3–4). It is, moreover, essential that his confession shall be by spoken words of his lips, and all that which he concluded in his heart shall be formed in speech.²Yoma, 57b; Shabbat, 121. G.

He who confesses by speech but has not his heart's consent to abandon his erstwhile conduct, behold him, he is like one taking an immersion of purification and in his grasp is an impure creeping thing, when he knows the immersion to be of no value till he cast away the impure creeping thing. Even so it is advised to do, saying: "But whoso confesseth and forsaketh them shall shall obtain mercy" (Pro. 28. 13). In confessing to God, it is obligatory to name the sin, even as it is said: "Oh, this people have sinned a great sin, and have made them a god of gold" (Ex. 32.31).³Ta’anit, 16a; Yoma, 86b. C.

Do not say that no repentance is needed save on sins to which action is attached, for example: prostitution, robbery, or theft. For even as it is necessary for man to repent from such, so it is necessary for him to search his bad tendencies, to turn in repentance from anger, from hatred, from jealousy, from deceit, from pursuing after wealth, honor, feasting and such like these; yea, from all of these it is necessary for him to turn in repentance. Indeed these iniquities are more grievous and more difficult for a man to be separated from than those which require action, for on such the prophet Isaiah said: "Let the wicked forsake his way, and the man of iniquity his thoughts" (Is. 55.7).