Sayyiduna Ibn al-Khasasiyah al-Sadusi (may Allah be pleased with him) said: I came to the Messenger of Allah (peace and blessings be upon him) to give him my pledge of allegiance, and he (peace and blessings be upon him) set these conditions for me: "That you bear witness that there is no god worthy of worship except Allah and that Muhammad (peace and blessings be upon him) is His servant and Messenger, that you offer the five prayers, fast Ramadan, pay the zakah, perform Hajj to the House, and strive (jihad) in the path of Allah." I said: O Messenger of Allah, two of these I cannot manage. As for zakah, by Allah, I have only ten camels, which serve my family for riding and for carrying loads. As for jihad, people say that whoever turns his back (in battle) has incurred the wrath of Allah, and I fear that when I face fighting my heart will weaken and I will dislike death. The Messenger of Allah (peace and blessings be upon him) withdrew his hand and shook it, then said: "No charity and no jihad, then how will you enter Paradise?" So I gave him (peace and blessings be upon him) my pledge on all of them.
Hadith Referenceالمعجم الكبير للطبراني / باب الباء / 1222