On the authority of Abu Abdullah Jabir bin Abdullah al-Ansari (may Allah be pleased with him):
A man questioned the Messenger of Allah (peace be upon him) and said: "Do you think that if I perform the obligatory prayers, fast in Ramadan, treat as lawful that which is halal, and treat as forbidden that which is haram, and do not increase upon that [in voluntary good deeds], then I shall enter Paradise?" He (peace be upon him) replied, "Yes."