God's door opens the same way the tenth time as the first. That is the sentence worth holding on to when the sin you are bringing is the one you have brought before, in the same words, with a resolve that did not hold.
What makes a repeated wrong heavy is the way it puts your own repentance in doubt. The mind reaches for the obvious verdict, that the earlier remorse was counterfeit, and that shame runs harder than the shame of the act. In Surah Yusuf the confession is that the lower self urges relentlessly toward harm, and the Qur'an says elsewhere that without God's grace not one of you would ever be purified. Neither line describes people who get it right on the first attempt.
Verse 3:135 praises those who seek forgiveness and do not persist in what they did, knowingly. Persisting in that sense describes a settled decision, the shrug that stops asking and treats the matter as closed. Falling, hating it, and turning back again is a different posture altogether, however worn out the turning has started to feel.
Repetition usually has a shape, and looking at it plainly is part of meaning the repentance: the hour, the room, the phone, the company, the loneliness sitting underneath it. Changing what surrounds the act tends to do more than promising harder.
The verses gathered here are for the person on their tenth return rather than their first. If the weight you carry sits more on the wrong itself than on its repetition, verses about repentance stay closer to that, and mercy and forgiveness gathers what the Qur'an says about a mercy wider than anyone's record.
3:135 — And those who, when they commit an indecency or wrong themselves, remember God and seek forgiveness for their sins — and who forgives sins but God? — and they do not persist in what they did, knowingly.
12:53 — And I do not absolve myself — the lower self urges relentlessly toward harm, except where my Lord shows mercy. Indeed, my Lord is forgiving and merciful.
4:17 — God accepts repentance only from those who do wrong in ignorance and then turn back soon after — these are the ones God turns toward in mercy, and God is all-knowing, all-wise.
20:82 — And indeed, I am ever-forgiving to whoever repents, believes, does righteous deeds, and then stays on the path of guidance.
24:21 — You who believe, do not follow the footsteps of Satan. Whoever follows the footsteps of Satan — he commands what is shameful and wrong. Were it not for God's grace upon you and his mercy, not one of you would ever be purified, but God purifies whom he wills, and God is all-hearing, all-knowing.
53:32 — Those who avoid the major sins and shameful deeds, save for slight lapses — indeed, your Lord is vast in forgiveness. He knows you best, from when he brought you forth from the earth and when you were hidden in the wombs of your mothers. So do not claim purity for yourselves; he knows best who is mindful of him.
5:39 — But whoever repents after their wrongdoing and sets things right — God will turn to them in mercy. Indeed, God is forgiving, merciful.
71:10 — I said: ask forgiveness of your Lord — indeed, he is ever-forgiving.