Performing prayer while moving is permissible only for one who is afraid of harm in his life or wealth until the end of the time of prayer; because of the words of God Almighty that has said: ﴿فَإِنْ خِفْتُمْ فَرِجَالًا أَوْ رُكْبَانًا﴾[1]; “And if you fear, then (perform prayer) on foot or riding.” So if he performs prayer while moving and then his fear goes away and there is still time for prayer, he must repeat it; because of the words of God Almighty that has said: ﴿فَإِذَا أَمِنْتُمْ فَاذْكُرُوا اللَّهَ﴾[2]; “And when you are safe, remember God,” and said: ﴿فَإِذَا اطْمَأْنَنْتُمْ فَأَقِيمُوا الصَّلَاةَ﴾[3]; “And when you are secure, perform prayer,” and one who performs prayer while moving must perform what he can of it while facing the Qiblah and in a normal way, and what he cannot of it, toward any direction and in any way he can; because of the words of God Almighty that has said: ﴿لَا يُكَلِّفُ اللَّهُ نَفْسًا إِلَّا وُسْعَهَا﴾[4]; “God does not impose upon anyone an obligation but to the extent of his ability,” and said: ﴿وَمَا جَعَلَ عَلَيْكُمْ فِي الدِّينِ مِنْ حَرَجٍ﴾[5]; “And He has laid upon you no hardship in religion,” and he must at least say the opening takbeer while facing the Qiblah; as one of our companions informed us, he said:

«سَأَلْتُ الْمَنْصُورَ عَنِ الصَّلَاةِ فِي الطَّيَّارَةِ، فَقَالَ: اسْتَقْبِلِ الْقِبْلَةَ وَكَبِّرْ، ثُمَّ اسْتَقْبِلْ حَيْثُ تَسْتَقْبِلُ الطَّيَّارَةُ، وَلَا تُصَلِّ فِيهَا مَكْتُوبَةً إِلَّا وَأَنْتَ خَائِفٌ، قُلْتُ: أُصَلِّي فِيهَا جَالِسًا؟ قَالَ: تُصَلِّي قَائِمًا أَبَدًا، فَإِنْ لَمْ تَسْتَطِعْ فَقَاعِدًا، فَإِنْ لَمْ تَسْتَطِعْ فَعَلَى جَنْبِكَ، فَإِنْ لَمْ تَسْتَطِعْ فَبِالْإِيمَاءِ، فَإِنْ لَمْ تَسْتَطِعْ فَبِالنِّيَّةِ، وَهَذَا كَقَوْلِ الْحَدَّادِ لِفَتَاهُ: مُتْ وَأَنْتَ نَافِخٌ!»; “I asked Mansoor about performing prayer on an airplane, so he said: ‘Turn toward the Qiblah and say, “Allahu Akbar,” then turn toward whichever direction the airplane turns, and do not perform any obligatory prayer on it unless you are afraid (that you will miss it)!’ I said: ‘Should I perform prayer while sitting on it?’ He said: ‘You always perform prayer while standing, and if you cannot, while sitting, and if you cannot, while on your side, and if you cannot, with a gesture, and if you cannot, with intention, and this is like the words of the blacksmith (in the well-known proverb) who said to his apprentice: Die and blow!’[6]”