It is narrated from Sayyiduna Ma'iz al-Tamimi (may Allah be pleased with him) that a man asked the Prophet (peace and blessings be upon him): Which deed is best? He (peace and blessings be upon him) said: "Faith in Allah, and jihad in His path." Then the questioner's thigh began to tremble, and he said: Then what? He (peace and blessings be upon him) said: "Then a deed that is better than all other deeds, except something like an accepted Hajj."
Hadith Referenceالمعجم الكبير للطبراني / باب الميم / 17942