What are the evil deeds that nullify good deeds and erase them from one's record?

Deeds are not nullified except by disbelief, as indicated by the verse: "Say, 'Spend willingly or unwillingly; never will it be accepted from you. Indeed, you were a defiantly disobedient people.' And what prevented their expenditures from being accepted from them was only that they had disbelieved in Allah and in His Messenger." This is supported by the statement of Ibn Taymiyyah: "Nothing nullifies deeds except disbelief, for whoever dies upon faith will inevitably enter Paradise."

As for evil deeds, the Sunnis have differed on whether they nullify good deeds. Some, like Ibn Qudamah, denied this, while others, like Shaykh al-Islam Ibn Taymiyyah and his student Ibn al-Qayyim, affirmed it. They held that some acts of disobedience and innovation nullify the reward of equivalent good deeds, citing the Almighty's saying: "O you who have believed, do not raise your voices above the voice of the Prophet or be loud to him in speech like the loudness of some of you to others, lest your deeds become worthless while you perceive not," and His saying: "O you who have believed, do not invalidate your charities with reminders [of it] or injury," and the Prophet's (peace be upon him) saying: "Whoever misses the Asr prayer, his deeds are nullified," and the Almighty's saying in the Hadith Qudsi: "Who is it that swears by Me that I will not forgive so-and-so? I have forgiven so-and-so and nullified your deeds."

The Salaf (early generations) feared the nullification of deeds by major sins, as Al-Hasan said regarding the Almighty's saying: "And do not invalidate your deeds" – meaning by sins and major transgressions. The concern is not merely in performing the deed, but in preserving it from what corrupts and nullifies it.