Is shaking hands (musafaha) in the mosque after prayer considered an innovation (bid‘ah)?

Musafaha is a form of social interaction expressed by shaking hands as a sign of friendship and peace. The Prophet Muhammad (peace be upon him) attached great importance to this practice (Bukhari, Isti’dhan, 27; Abu Dawud, Adab, 153 [5211]) and encouraged it by saying, “When two Muslims meet and shake hands, their sins are forgiven before they part.” (Abu Dawud, Adab, 153 [5212]).

There is no religious objection to shaking hands after prayer, as it fosters friendship, tolerance, and unity among Muslims. (Ibn Abidin, Radd al-Muhtar, 6/381) However, it is not appropriate to turn shaking hands after prayer, whether inside or outside the mosque, into a formal ceremony or to consider it an inseparable part of congregational prayer.

Source: T.C. Diyanet İşleri Başkanlığı, Din İşleri Yüksek Kurulu