Your Apostle ﷺ teaches you about everything, even about excrement. He replied: Yes, he has forbidden us to face the Qibla at the time of excretion or urination, or cleansing with right hand or with less than three pebbles, or with dung or bone.  

قِيلَ لَهُ قَدْ عَلَّمَكُمْ نَبِيُّكُمْ ﷺ كُلَّ شَىْءٍ حَتَّى الْخِرَاءَةَ قَالَ فَقَالَ أَجَلْ لَقَدْ نَهَانَا أَنْ نَسْتَقْبِلَ الْقِبْلَةَ لِغَائِطٍ أَوْ بَوْلٍ أَوْ أَنْ نَسْتَنْجِيَ بِالْيَمِينِ أَوْ أَنْ نَسْتَنْجِيَ بِأَقَلَّ مِنْ ثَلاَثَةِ أَحْجَارٍ أَوْ أَنْ نَسْتَنْجِيَ بِرَجِيعٍ أَوْ بِعَظْمٍ  

I see that your friend even teaches you about the excrement. He replied; Yes, he has in fact forbidden us that anyone amongst us should cleanse himself with his right hand, or face the Qibla. He has forbidden the use of dung or bone for it, and he has also instructed us not to use less than three pebbles (for this purpose).  

لَنَا الْمُشْرِكُونَ إِنِّي أَرَى صَاحِبَكُمْ يُعَلِّمُكُمْ حَتَّى يُعَلِّمَكُمُ الْخِرَاءَةَ فَقَالَ أَجَلْ إِنَّهُ نَهَانَا أَنْ يَسْتَنْجِيَ أَحَدُنَا بِيَمِينِهِ أَوْ يَسْتَقْبِلَ الْقِبْلَةَ وَنَهَى عَنِ الرَّوْثِ وَالْعِظَامِ وَقَالَ لاَ يَسْتَنْجِي أَحَدُكُمْ بِدُونِ ثَلاَثَةِ أَحْجَارٍ  

The Messenger of Allah ﷺ forbade the use of bone or the droppings of camels for wiping (after excretion).  

أَنَّهُ سَمِعَ جَابِرًا يَقُولُ نَهَى رَسُولُ اللَّهِ ﷺ أَنْ يُتَمَسَّحَ بِعَظْمٍ أَوْ بِبَعْرٍ  

The Apostle of Allah ﷺ said: Whenever you go to the desert, neither turn your face nor turn your back towards the Qibla while answering the call of nature, but face towards the east or the west. Abu Ayyub said: When we came to Syria we found that the latrines already built there were facing towards the Qibla. We turned our faces away from them and begged forgiveness of the Lord. He said: Yes.  

أَنَّ النَّبِيَّ ﷺ قَالَ إِذَا أَتَيْتُمُ الْغَائِطَ فَلاَ تَسْتَقْبِلُوا الْقِبْلَةَ وَلاَ تَسْتَدْبِرُوهَا بِبَوْلٍ وَلاَ غَائِطٍ وَلَكِنْ شَرِّقُوا أَوْ غَرِّبُوا قَالَ أَبُو أَيُّوبَ فَقَدِمْنَا الشَّامَ فَوَجَدْنَا مَرَاحِيضَ قَدْ بُنِيَتْ قِبَلَ الْقِبْلَةِ فَنَنْحَرِفُ عَنْهَا وَنَسْتَغْفِرُ اللَّهَ قَالَ نَعَمْ  

When any one amongst you squats for answering the call of nature, he should neither turn his face towards the Qibla nor turn his back towards it.  

عَنْ رَسُولِ اللَّهِ ﷺ قَالَ إِذَا جَلَسَ أَحَدُكُمْ عَلَى حَاجَتِهِ فَلاَ يَسْتَقْبِلِ الْقِبْلَةَ وَلاَ يَسْتَدْبِرْهَا  

I was offering my prayer in the mosque and Abdullah b. Umar was sitting there reclining with his back towards the Qibla. After completing my prayer. I went to him from one side. Abdullah said: People say when you go to the latrine, you should neither turn your face towards the Qibla nor towards Bait-ul-Maqdis. 'Abdullah said (farther): I went up to the roof of the house and saw the Messenger of Allah ﷺ squatting on two bricks for relieving himself with his face towards Bait-al-Maqdis.  

عَبْدُ اللَّهِ يَقُولُ نَاسٌ إِذَا قَعَدْتَ لِلْحَاجَةِ تَكُونُ لَكَ فَلاَ تَقْعُدْ مُسْتَقْبِلَ الْقِبْلَةِ وَلاَ بَيْتِ الْمَقْدِسِ قَالَ عَبْدُ اللَّهِ وَلَقَدْ رَقِيتُ عَلَى ظَهْرِ بَيْتٍ فَرَأَيْتُ رَسُولَ اللَّهِ ﷺ قَاعِدًا عَلَى لَبِنَتَيْنِ مُسْتَقْبِلاً بَيْتَ الْمَقْدِسِ لِحَاجَتِهِ  

I went up to the roof of the house of my sister Hafsa and saw the Messenger of Allah ﷺ relieving himself facing Syria. with his back to the Qibla.  

رَقِيتُ عَلَى بَيْتِ أُخْتِي حَفْصَةَ فَرَأَيْتُ رَسُولَ اللَّهِ ﷺ قَاعِدًا لِحَاجَتِهِ مُسْتَقْبِلَ الشَّامِ مُسْتَدْبِرَ الْقِبْلَةِ