When you think in a focused manner, you develop intellectually. In this way, you can understand matters more deeply and can analyze issues properly. When Umar ibn al-Khattab was caliph, Jerusalem was conquered by the Muslims. The Muslims had besieged the forts of Jerusalem's rulers. These rulers refused to surrender except on the condition that the caliph himself should come to sign the terms of agreement. Umar received this message and set out from Madinah towards Jerusalem. When he reached Jerusalem, he went inside a church, known as the Church of Resurrection. This was the spot where negotiations were conducted between Umar and the priests. While discussions were going on, it was time for Asr prayer. Umar said that he would like to pray. The main priest told Umar that he could pray in the Church itself, however, Umar refused to do so. He replied that he would instead pray at a stone's throw distance from the Church. The reason Umar gave was that if he prayed in the Church of Resurrection, the Muslim generations after him would say: "Our Caliph prayed here, so we will build a mosque at this place." This would have undoubtedly led to a conflict. Umar's example shows that when a person does not allow himself to get distracted by trivial issues, he can think with great foresight. This is what really happened. Later in the Umayyad period, when Muslims came to know the spot where Umar had prayed, they built a mosque, which is today known as the Mosque of Umar. This mosque is outside the precincts of the Church of Resurrection. Had Umar prayed inside the Church, Muslims would have later tried to build a mosque there, which could have become a cause for great discord between Christians and Muslims.
