Sa‘eed bin Musayyib narrates that Hadhrat Umar 
once intended to take the house* of Hadhrat Abbas to include it in the Masjid. However, Hadhrat Abbas refused to hand the house over. When Hadhrat Umar resolved that he would certainly have possession of the house, Hadhrat Abbas proposed that they appoint Hadhrat Ubay bin Ka‘b to pass judgement between them. Hadhrat Umar agreed and they both approached Hadhrat Ubay . After they had related the matter to him, Hadhrat Ubay said, “Allah sent revelation to Hadhrat Sulayman bin Dawud instructing him to construct Baytul Maqdis [in Jerusalem]. The land belonged to a man whom Hadhrat Sulayman 
approached to buy it from him. However, when Hadhrat Sulayman handed over the money to the man, he [the man] asked, ‘Is this price that you are paying better or is that which you are taking from me better?’ Hadhrat Sulayman replied, ‘Certainly that which I am taking from you is better.’ ‘In that case,’ said the man, ‘I shall not accept it.’
Hadhrat Sulayman then gave the man a higher price. The man then did the same thing two or three times until Hadhrat Sulayman made the condition with him, ‘I am buying the land from you at the price you fix. You may therefore not ask me which of the two is better.’ Hadhrat Sulayman took the purchased land from him at the price he fixed, which happened to be twelve thousand Qintar of gold (one Qintar equals four thousand gold coins). Hadhrat Sulayman then felt that the amount was too big to give the man. Allah then sent revelation to him saying, ‘If you are paying him from something that is your own, then you know best (what you have to do). However, if you are paying from what We have provided for you, then give him whatever he is pleased with.’ Hadhrat Sulayman then paid the amount.”
Hadhrat Ubay continued, “I feel that Abbas has a greater right to his house, which cannot be taken from him until he is pleased.” Hadhrat Abbas then said, ‘Since you have made the decision in my favour, I wish to make it Sadaqah [a charitable gift] for the Muslims.’
[Hayatus Sahabah (The Lives of the Companions), by Maulana Muhammad Yusuf Kandhelwi, excerpted from the English translation by Mufti Afzal Hoosen Elias, Zam Zam Publishers, Karachi, June 2013, vol. 2, pp. 133-134 (related by Abdur Razzaq, as quoted in Kanzul Ummal vol. 4 p. 260. Also related by Ibn Sa‘d vol. 4 p. 13. Ibn Asakir relates a similar narration, as do Bayhaqi and Ya‘qub bin Sulayman – quoted in Kanzul Ummal vol. 7 p. 65). Words in square brackets have been added.]
*His house was next door to Masjidun Nabawi
The Caliphate 