What is the ultimate difference between Wajib and Fardh?
Jazakallah for your time and efforts
Fardh is an act of Shariah which has been established through ‘Nass Qat’ee’. I.e. such a strong evidence which is unambiguous and clear. (e.g. the Quraan) whereas Wajib is that Amal which is established through a lesser degree evidence.
Qiyaam, Ruku, Sujood are Fardh as they are in the Quraan. Tashahhud and Duae-Qunoot are Wajib as they are not in the Quraan. Another difference is that with Fardh, both practice and belief in it is compulsory whereas with Wajib, only practice is compulsory and believing that it’s Wajib is not compulsory.