I have dictated the hadith of Sayyiduna Umar bin Khattab (may Allah be pleased with him) regarding Jibreel (peace be upon him) asking the Prophet Muhammad (peace and blessings be upon him) about Islam, in the Book of Purification.

Hazrat Ikrimah bin Khalid bin As narrates to Sayyiduna Tawus that a man said to Sayyiduna Abdullah bin Umar (may Allah be pleased with them), "Will you not perform Jihad?" So Abdullah bin Umar (may Allah be pleased with them) replied, "Indeed, I heard the Messenger of Allah (peace and blessings be upon him) say: 'Islam is built upon five things: bearing witness that there is no deity worthy of worship except Allah, establishing prayer, giving zakat, fasting in Ramadan, and performing Hajj to the House of Allah.'"

Sayyiduna Ibn Umar (may Allah be pleased with them both) narrates from the Noble Prophet (peace and blessings be upon him) that he (peace be upon him) said: "Islam is built upon five things: bearing witness that there is no true deity except Allah and that Muhammad (peace and blessings be upon him) is the Messenger of Allah, establishing prayer, giving zakat, performing Hajj to the Sacred House, and fasting in the blessed month of Ramadan." Imam Abu Bakr (may Allah have mercy on him) narrates from his teacher Muhammad bin Yahya, with his chain, from Sayyiduna Ibn Umar (may Allah be pleased with them both) that the Messenger of Allah (peace and blessings be upon him) said, and narrated as in the aforementioned narration. Imam Abu Bakr (may Allah have mercy on him) says that I have mentioned the chains of this hadith in the Book of Faith.