and be Cautious (وَلْيَتَلَطَّفْ)

 The word in the middle of The Quran: وَلْيَتَلَطَّفْ , written in bold in most mushafs, advises the believer to be cautious. 

Stoning to Death   

وَكَذَٰلِكَ بَعَثْنَاهُمْ لِيَتَسَاءَلُوا بَيْنَهُمْ قَالَ قَائِلٌ مِّنْهُمْ كَمْ لَبِثْتُمْ قَالُوا لَبِثْنَا يَوْمًا أَوْ بَعْضَ يَوْمٍ قَالُوا رَبُّكُمْ أَعْلَمُ بِمَا لَبِثْتُمْ فَابْعَثُوا أَحَدَكُم بِوَرِقِكُمْ هَٰذِهِ إِلَى الْمَدِينَةِ فَلْيَنظُرْ أَيُّهَا أَزْكَىٰ طَعَامًا فَلْيَأْتِكُم بِرِزْقٍ مِّنْهُ وَلْيَتَلَطَّفْ وَلَا يُشْعِرَنَّ بِكُمْ أَحَدًا

إِنَّهُمْ إِن يَظْهَرُوا عَلَيْكُمْ يَرْجُمُوكُمْ أَوْ يُعِيدُوكُمْ فِي مِلَّتِهِمْ وَلَن تُفْلِحُوا إِذًا أَبَدًا

And in like manner We awakened them that they might question one another. A speaker from among them said: How long have ye tarried? They said: We have tarried a day or some part of a day, (Others) said: Your Lord best knoweth what ye have tarried. Now send one of you with this your silver coin leaf unto the city, and let him see what food is purest there and bring you a supply thereof. Let him be courteous subtle and let no man know of you.
For they, if they should come to know of you, will stone you or turn you back to their religion; then ye will never prosper.

[Al-Quran 18:19-20, Translation: Pickthal; edited in italics for clarity]

They advise the person who is being sent into town is to be لْيَتَلَطَّفْ lest his true identity is discovered, and he stoned to death or forced to revert to polytheism. Some translate this word as cautious, others as courteous. This word is derived from the root ل ط ف which forms Allah ﷻ 's name اللَّطِيفُ generally translated as The All-Subtle: 

Excerpt from corpus.quran.com

Surah al-Kahf contains guidance and protection for the believers. The Quran's word count reaches its mid-point in Surah al-Kahf, ayat 19. The word in the middle of The Quran: وَلْيَتَلَطَّفْ , written in bold in most mushafs, advises the believer to be cautious. In this day and age, everything is online, and it is easy to obtain entire record of activities and statements of people. As the world is heading towards the end times, and the net of control is increasingly powerful, the believers would be well-advised to keep a low profile, especially when their faith and/or their lives are in danger. 

The ashab-e-kahf had taken a stand for their faith, and then went into hiding in a kahf (pit-cave). They fell asleep for a long time. When they were awakened, they needed to purchase food. One of them was being sent to the city, where he was supposed to purchase some nourishing food with his waraq (leaf). 

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Also read: 

Purchase with Your Leaf 

Detailed Guidance in Surah alKahf (subtitle: Stoning to Death)