Sunan Ibn Majah
Sunan Ibn Majah 763
حَدَّثَنَا مُحَمَّدُ بْنُ رُمْحٍ الْمِصْرِيُّ، أَنْبَأَنَا اللَّيْثُ بْنُ سَعْدٍ، عَنْ نَافِعٍ، عَنْ عَبْدِ اللَّهِ بْنِ عُمَرَ، قَالَ رَأَى رَسُولُ اللَّهِ ـ صلى الله عليه وسلم ـ نُخَامَةً فِي قِبْلَةِ الْمَسْجِدِ وَهُوَ يُصَلِّي بَيْنَ يَدَىِ النَّاسِ فَحَتَّهَا ثُمَّ قَالَ حِينَ انْصَرَفَ مِنَ الصَّلاَةِ " إِنَّ أَحَدَكُمْ إِذَا كَانَ فِي الصَّلاَةِ كَانَ اللَّهُ قِبَلَ وَجْهِهِ فَلاَ يَتَنَخَّمَنَّ أَحَدُكُمْ قِبَلَ وَجْهِهِ فِي الصَّلاَةِ " .
Unreviewed translation. All hadiths in this collection are available in five languages. Titles and introductions may remain in Arabic.
Muhammad ibn Ramh al-Misri informed us: Al-Layth ibn Sa'd informed us, from Nafi', from 'Abdullah ibn 'Umar, who said: The Messenger of Allah (peace and blessings be upon him) saw spittle in the mosque's direction of prayer while he was praying in front of the people. He scraped it away. After completing the prayer, he said: ‘When one of you is praying, Allah is before him; so let no one spit in front of himself while praying.’
Notes and open questions — unreviewed
The source specifies the mosque's qiblah (direction of prayer) and uses a direct statement about Allah being before the worshipper.