Is a person who cleanses with fewer than three wipes, yet achieves purification, sinful, or are their prayer and ablution invalid, as the Shafi'is say?

For purification with stones or their equivalents, such as paper tissues, it is a condition that cleanliness (al-inqa’) is achieved and that the wipes are completed to three. If cleanliness is not achieved with three wipes, it is obligatory to add more until cleanliness is attained, and it is recommended to end with an odd number. However, if cleanliness is achieved with fewer than three, it is obligatory to complete them to three, and less than that is not sufficient; otherwise, the impurity is not removed.

Whoever prays after performing istijmar (purification with stones/wipes) without completing the required number, their prayer is invalid according to the majority of scholars (Shafi’is and Hanbalis), because avoiding impurity is a condition for the validity of prayer, and because the removal of the impurity has not been confirmed.

Malik and Dawud held the view that it is permissible to suffice with fewer than three if cleanliness is achieved, interpreting the command for three wipes as reflecting that cleanliness usually cannot be attained without them.

However, the majority of jurists believe their opinion is more sound due to the strength of their evidence, such as the hadiths of Salman, Abu Hurairah, Aisha, Khuzaimah, and Ibn Mas’ud (may Allah be pleased with them all), which stipulate three wipes and indicate that it is not permissible to suffice with fewer than three even if cleanliness is achieved, because a stone does not completely remove the trace as water does, and therefore a specific number was stipulated for it.