Abu Ayyub al-Ansari

Abu Ayyub al-Ansari (died 674) — born Khalid bin Zayd bin Kulayb in Yathrib — hailed from the tribe of Banu Najjar and was a close companion (Arabic: الصحابه, sahaba) of Muhammad. He was named after the biblical Job. Abu Ayyub was one among the Ansar (Arabic: الأنصار, meaning aiders, helpers or patrons) of early Muslim history or those who supported Muhammad after the hegira (migration) to Medina in 622. The patronym Abu Ayyub, means father (abu) of Ayyub. Abu Ayyub died of dysentery during the First Arab Siege of Constantinople.
When Muhammad arrived in Medina, he was offered accommodation by all of its inhabitants. It was decided to leave his camel to walk freely and where ever it sits and whomsoever's house is near to choose as Muhammad's temporary residence and the camel sat near Abu Ayyub al-Ansari 's house who belonged to Bani An-Najjar the best of the tribes in Medina Sahih Bukari Book #73, Hadith #79. When Abu Ayub Al Ansari cooked a lunch only for Muhammad and Abubakr Muhammad ordered to invite the neighbourhood to their surprise which were about 180 people who ate satisfactorily and was a miracle.
Waqif Of Al-Masjid an-Nabawi: The land of Al-Masjid an-Nabawi was owned by Sahal and Suhayl,and they knows that Profet Muhammad (SA) is interested about this land for Building Masjid so they came to profet (sa) and offered this land for free of cost but Profet (SA) fixed a price for the holly land why because they are teenagers and they lost their father; and this price is spend by Abu Ayyub al-Ansari (RA) He is the Waqif of Al-Masjid an-Nabawi on behalf of Profet Muhammad (sa)
Following the Muslim conquest of Egypt, Abu Ayyub moved to a house in Fustat adjacent to the mosque of Amr bin Al'aas which was completed in 642. Several other notable companions were his neighbors, including Zubayr ibn al-Awwam, Ubaida, Abu Dhar, Abdullah ibn Umar and Abdullah ibn Amr bin Al'aas.
He also led a distinguished military career. Of him it was said, "He did not stay away from any battle the Muslims fought from the time of Muhammad to the time of Muawiyah, unless he was engaged at the same time in another."

In a hadith in Qital-e Rome chapter of Sahih Muslim, Muhammad stated that the first army to conquer Constantinople will enter Paradise.

Muhammad ibn Jarir al-Tabari records a number of raids against the Byzantine Empire under the period A.H. 49 (9/2/669 - 28/1/670). Abu Ayyub was an old man, but that did not prevent him from enlisting. Shortly after engaging in battle, he fell ill and had to withdraw. Someone asked, "Do you need anything, Abu Ayyub?" To which Abu Ayyub replied, "Convey my salaams (Islamic greeting and farewell) to the Muslim armies and tell them, "Abu Ayyub urges you to penetrate deep into enemy territory, as far as you can go. That you should carry him with you, and that you should bury him under your feet at the walls of Constantinople." Then he died. The Muslim army fulfilled his request and pushed back the enemy's forces until they reached the walls of Constantinople where Abu Ayyub was buried.

About this battle, Aslam-ibn `Imran narrates that when they were fighting the Byzantines, a Muslim soldier penetrated deep into enemy ranks. People exclaimed, "Subhan Allah! He has contributed to his own destruction." Abu Ayyub al-Ansari stood up and answered, "O people! You give this interpretation to this verse, whereas it was revealed concerning us the Ansar. When Allah had actually given honor to Islam and its supporters had become many, whereupon some of us secretly said to one another... 'Our wealth has been depleted, and Allah has given honor to Islam and its supporters have become many, let us stay amidst our wealth and make up what has been depleted of it.' Thereupon, Allah revealed to Muhammad, 'And spend in the Path of God (فِي سَبِيلِ اللّهِ), and do not contribute to your own destruction'... refuting what we had said. So, destruction lay in staying with our wealth and repleting it and abandoning combat."

After the Conquest of Constantinople by the Ottoman Turks, a tomb was constructed above Abu Ayyub's grave and a mosque built in his honor. From that point on, the area now known as the locality of Eyüp has become sacred and many Ottoman officials requested burial in proximity of Abu Ayyub

Abu Ayyub al-Ansari is credited with narrating many sayings of Muhammad. Well-known examples of these include:

• Allah's Apostle said, "It is not lawful for a man to desert his brother Muslim for more than three nights. (It is unlawful for them that) when they meet, one of them turns his face away from the other, and the other turns his face from the former, and the better of the two will be the one who greets the other first."
• Abu Ayyub al-Ansari narrates that on the night of Mi'raj, Muhammad passed by Ibrahim (Abraham). Ibrahim asked, "O Jibreel, who is with you?" Jibreel answered, "Muhammad." Ibrahim said to him, "Command your Ummah to plant saplings of Paradise plentifully, as the soil of Paradise is fertile and its plain is spacious." It was asked, "What are the saplings of Paradise?" He replied, "La hawla wa la quwwata illa billah (Arabic "لا حول ولاقوة إلا بالله".)"

• Both are recorded in Sahih Bukhari
• from Musnad Ahmad ibn Hanbal, Majma al-Zawa'id