Yahya b. Ya`mur said

The first to speak on Divine decree in al-Basrah was Ma`bad al Juhani. I and Humaid b. `Abd al-Rahman al-Himyari proceeded to perform Hajj or `Umrah. We said : would that we meet any of the Companions of the Messenger of Allah (ﷺ) so that we could ask him about what they say with regard to divine decree. So Allah helped us to meet `Abd Allah b. `Umar who was entering the mosque. So I and my companion surrounded him, and I thought that my companion would entrust me the task of speaking to him. Then I said : Abu ‘Abd al-Rahman, there appeared on our side some people who recite the Qur'an and are engaged in the hair-splitting of knowledge. They conceive that there is no Divine decree and everything happens freely without predestination. He said : When you meet those people, tell them that I am free from them, and they are free from me. By Him by Whom swears ‘Abd Allah b. ‘Umar, if one of them has gold equivalent to Uhud and he spends it, Allah will not accept it from him until he believes in Divine decree. He then said : ‘Umar b. Khattab transmitted to me a tradition, saying : One day when we were with the Messenger of Allah (ﷺ) a man with very white clothing and very black hair came up to us. No mark of travel was visible on him, and we did not recognize him. Sitting down beside the Messenger of Allah (ﷺ), leaning his knees against his and placing his hands on his thighs, he said : tell me, Muhammad , about Islam. The Messenger of Allah (ﷺ) said : Islam means that you should testify that there is no god but Allah, and Muhammad is Allah’s Apostle, that you should observe prayer, pay Zakat, fast during Ramadan, and perform Hajj to the house (i.e., Ka`bah), If you have the means to go. He said : You have spoken the truth. We were surprised at his questioning him and then declaring that he spoke the truth. He said : Now tell me about faith. He replied : It means that you should believe in Allah, his angels, his Books, his Apostles and the last day, and that you should believe in the decreeing both of good and evil. He said : You have spoken the truth. He said : now tell me about doing good (ihsan). He replied: It means that you should worship Allah as though you are seeing him; if you are not seeing him, he is seeing you. He said: Now tell me about the hour. He replied : The one who is asked about it is no better informed than the one who is asking. He said : Then tell me about its signs. He replied : That a maidservant should beget her mistress, and that you should see barefooted, naked, poor men and shepherds exalting themselves in buildings. ‘Umar said : He then went away, and I waited for three days, then he said : Do you know who the questioner was, `Umar? I replied : Allah and his Apostle know best. He said : He was Gabriel who came to you to teach you your religion.