Hazrat Shaikh Moulana Muhammad Zakariyya (rahmatullahi ‘alaih) once mentioned:

I heard my respected father, Moulana Muhammad Yahya Kandhelwi (rahmatullahi ‘alaih) mention on many occasions: “The reward one acquires through following the mubaarak sunnah of Sayyiduna Rasulullah (sallallahu ‘alaihi wasallam) surpasses the reward one acquires through carrying out any other optional ‘ibaadat not recorded in the sunnah. Hence, if one enters the toilet and relieves oneself in the sunnah manner, and one does so with the niyyat of emulating the mubaarak sunnah of Sayyiduna Rasulullah (sallallahu ‘alaihi wasallam), one will earn more reward than performing nafl rakaats of salaah which have not been recorded in the sunnah.” (Qutbul Aqtaab Hazrat Shaikhul Hadeeth Moulana Muhammad Zakariyya (rahmatullahi ‘alaih) pg. 70)

Source: Ihyaauddeen.co.za