Sahih al-Bukhari — Belief — Hadith No: 46
Translation
Narrated Talha bin 'Ubaidullah: A man from Najd with unkempt hair came to Allah's Messenger (ﷺ) and we heard his loud voice but could not understand what he was saying, till he came near and then we came to know that he was asking about Islam. Allah's Messenger (ﷺ) said, "You have to offer prayers perfectly five times in a day and night (24 hours)." The man asked, "Is there any more (praying)?" Allah's Messenger (ﷺ) replied, "No, but if you want to offer the Nawafil prayers (you can)." Allah's Messenger (ﷺ) further said to him: "You have to observe fasts during the month of Ramadan." The man asked, "Is there any more fasting?" Allah's Messenger (ﷺ) replied, "No, but if you want to observe the Nawafil fasts (you can.)" Then Allah's Messenger (ﷺ) further said to him, "You have to pay the Zakat (obligatory charity)." The man asked, "Is there any thing other than the Zakat for me to pay?" Allah's Messenger (ﷺ) replied, "No, unless you want to give alms of your own." And then that man retreated saying, "By Allah! I will neither do less nor more than this." Allah's Messenger (ﷺ) said, "If what he said is true, then he will be successful (i.e. he will be granted Paradise)