Yahya bin Yamar reported,

Someone said to Ibn Umar, "We have some men among us who claim that matters are decided anew, and that if they wish they can act, and if they wish they need not act."He replied, "Tell them that I disown them and they disown me." Then he said, "Jibreel came to the Prophet ﷺ and said, 'Muhammad, what is Islam?'He answered, 'Islam is that you associate nothing with Allah, establish the prayer, pay the zakat, fast Ramadan, and perform the pilgrimage to the House.'Jibreel asked, 'If I do that, am I a Muslim?'He said, 'Yes.'Jibreel said, 'You have spoken truly.' Then he asked, 'What is ihsan?'He answered, 'That you worship Allah the Exalted as though you see Him, for though you do not see Him, He sees you.'Jibreel asked, 'If I do that, am I a person of ihsan?'He said, 'Yes.'Jibreel said, 'You have spoken truly.' Then he asked, 'What is iman?'He answered, 'That you believe in Allah, His angels, His books, His messengers, the resurrection after death, Paradise and the Fire, and in the divine decree, all of it.'Jibreel asked, 'If I do that, am I a believer?'He said, 'Yes.'Jibreel said, 'You have spoken truly.'"

عن يحيى بن يعمر قلت

لابن عمر: إن عندنا رجالا يزعمون أن الأمر أنف بناءيده، وأن شاءوا تعملوا، وإن شاءوا لم يعملوا! فقال: أخبرهم أني منهم بريء، وأنهم مني برءاء، ثم قال: جاء جبريل يا عليه السلام إلى النبي ﷺ فقال: يا محمد ما الإسلام؟ فقال: الإسلام لا تشرك بالله شيئا، وتقيم الصلاة، وتؤتي الزكاة، وتصوم رمضان، وتحج البيت. قال: فإذا فعلت ذلك فأنا مسلم؟ قال: نعم. قال: صدقت. قال: فما الإيمان؟ قال: تعبد الله تعالى كأنك تراه فإنك لا تراه فإنه يراك. قال: فإذا فعلت ذلك فأنا مؤمن؟ قال: نعم. قال: صدقت. قال: فما الإحسان؟ قال: تؤمن بالله وملائكته، وكتبه، ورسله، والبعث من بعد الموت، والجنة والنار، والقدر كله. قال: فإذا فعلت ذلك فأنا محسن؟ قال: نعم. قال: صدقت.