Does a good deed become annulled due to ill intention or speech, and what is the correct understanding regarding such matters?

Fear of deeds being invalidated and of a bad reckoning is a great act of worship of the heart. It drives the righteous to hasten to do good deeds, as in the Almighty's saying: (And those who give what they give while their hearts are trembling because they know that to their Lord they are to return. It is those who hasten to good deeds, and they are the foremost in them). The Prophet, peace and blessings be upon him, explained this by saying that they are those who do good deeds and fear that they will not be accepted from them.

However, this fear should not turn into despair or despondency, because Allah does not wrong even an atom's weight, multiplies good deeds, and does not waste the reward of those who do good. Therefore, a Muslim should believe in Allah's justice and generosity, and that Allah does not punish those who are grateful and believe, as He said: (What would Allah do with your punishment if you are grateful and believe?). Fear thus motivates good deeds, honoring parents, and maintaining kinship ties.

The intended fear is that which drives one to action, not that which leads to despair, despondency, illness, or mental weakness. Praiseworthy fear yields caution, piety, devoutness, striving, worship, and contemplation.

It is necessary to balance fear and hope, so that neither one predominates over the other; rather, they should proceed together towards Allah, like a bird flying with its two wings. Allah is vast in generosity and benevolence, and He may forgive even a small deed for the sincere.