Al-Matalib al-'Aliyah 369 — The virtue of keeping to the mosque

It is narrated from Yunus bin Ubayd (may Allah have mercy on him) that he said: I asked Imam al-Hasan al-Basri (may Allah have mercy on him), or he was asked: "What is your view of this saying: 'As long as the servant remains in his place of prayer, he is counted as being continually in prayer'?" I asked: "Does it mean that particular seat and spot where he offered the prayer?" He replied: "No, rather it means the whole mosque."
The chain of this narration is hasan (good); Imam Musaddad bin Musarhad narrated it in his Musnad.