for, according to the Companions and the people of the Sunnah and the community, it is not nullified by a sin alone,
the reply is:
If invalidity means that one has not fully discharged one’s obligation to perform these acts, the same applies to obligatory faith: if one leaves out any part of it, one has not discharged that obligation in full. If it means that the act must be repeated, this does not apply without qualification. Hajj includes obligations whose omission does not require repeating it; rather, they are compensated for by a sacrificial offering. Likewise with prayer, according to most scholars: if obligations are omitted inadvertently or otherwise and repetition is required, it is required only when repetition is possible. Otherwise, whatever cannot be repeated remains an outstanding obligation, as with Friday prayer and the like.
If it means that one receives no reward for what one has done, that is not so. Rather, the Prophet, may Allah bless him and grant him peace, made clear in the hadith of the man who prayed incorrectly that someone who does not complete his prayer is rewarded for what he has done and is not like someone who has not prayed at all. Several hadiths state that obligatory acts of worship will be made complete on the Day of Resurrection through voluntary acts. If deficiencies in obligatory acts are made good through the reward of voluntary acts, this shows that one is credited for the obligatory acts one has performed. The same applies to faith: if someone leaves any part of it unfulfilled, he remains obliged to fulfill it. If it concerns something forbidden, he must repent of it; if it concerns an obligation, he must perform it. If he does not do so, his obligation remains undischarged, but he is rewarded for what he has done, just as with other acts of worship. The scriptural texts also establish that whoever has an atom’s weight of faith in his heart will be brought out of the Fire.
On this fundamental issue, the “Murji’ah” have departed from the explanations given in the Book and the Sunnah and from the statements of the Companions and those who followed them in righteousness. They have relied instead on their own opinions and on interpretations derived from their understanding of the language. This is the way of the people of innovation. Hence Imam Ahmad used to say:
“Most people’s errors arise from interpretation and analogy.”