Qur'an 4:101

وَإِذَا ضَرَبْتُمْ فِى ٱلْأَرْضِ فَلَيْسَ عَلَيْكُمْ جُنَاحٌ أَن تَقْصُرُوا۟ مِنَ ٱلصَّلَوٰةِ إِنْ خِفْتُمْ أَن يَفْتِنَكُمُ ٱلَّذِينَ كَفَرُوٓا۟ ۚ إِنَّ ٱلْكَـٰفِرِينَ كَانُوا۟ لَكُمْ عَدُوًّا مُّبِينًا

And when ye go forth in the land, it is no sin for you to curtail (your) worship if ye fear that those who disbelieve may attack you. In truth the disbelievers are an open enemy to you.