وَاِذَا ضَرَبۡتُمۡ فِى الۡاَرۡضِ فَلَيۡسَ عَلَيۡكُمۡ جُنَاحٌ اَنۡ تَقۡصُرُوۡا مِنَ الصَّلٰوةِ ۖاِنۡ خِفۡتُمۡ اَنۡ يَّفۡتِنَكُمُ الَّذِيۡنَ كَفَرُوۡاؕ اِنَّ الۡكٰفِرِيۡنَ كَانُوۡا لَـكُمۡ عَدُوًّا مُّبِيۡنًا
And when you travel in the land, there will be no sin on you if you shorten the Prayer (i.eoffer two instead of four mandatory cycles), if you fear that the disbelievers are likely to afflict you with distressAssuredly, the disbelievers are your open enemies.