Sahih Bukhari
Virtues of the Prayer Hall (Sutra of the Musalla)
Volume: 001 / Book Number: 009 / Hadith Number: 481
Narrated Yazid bin Al 'Ubaid:
I used to accompany Salama bin Al-Akwa' and he used to pray behind the pillar which was near the place where the Quran's were kept I said, "O Abu Muslim! I see you always seeking to pray behind this pillar." He replied, "I saw Allah's Apostle always seeking to pray near that pillar."