Prophet Muhammad's farewell sermon - worship Allah, perform your five daily prayers, fast during the month of Ramadan, and give your wealth in Zakat. Perform Haj if you can afford to

“O people, listen to me in earnest, worship Allah, perform your five daily prayers, fast during the month of Ramadan, and give your wealth in Zakat. Perform Haj if you can afford to." (Prophet Muhammad's farewell sermon)