Of course, he could have prayed discreetly so as not to be observed. He knew that his daily custom was well - known.
مَثَلًا ،‏ أَوْصَاهُمْ يَهْوَهُ :‏ « اُطْلُبُوا سَلَامَ ٱلْمَدِينَةِ ٱلَّتِي سَبَيْتُكُمْ إِلَيْهَا » .‏