We were with Prophet ﷺ and he asked for something to drink. A man from the company asked: Should we not give you nabidh (drink made from dates) to drink ? He replied : Yes . The man went quickly and bought a cup of nabidh. The Messenger of Allah ﷺ said: Why did you not cover it up even by putting a piece of wood on it ? Abu Dawud said: Al-Asma'i's version has: "You put it on it..."
كُنَّا مَعَ النَّبِيِّ ﷺ فَاسْتَسْقَى فَقَالَ رَجُلٌ مِنَ الْقَوْمِ أَلاَ نَسْقِيكَ نَبِيذًا قَالَ بَلَى قَالَ فَخَرَجَ الرَّجُلُ يَشْتَدُّ فَجَاءَ بِقَدَحٍ فِيهِ نَبِيذٌ فَقَالَ النَّبِيُّ ﷺ أَلاَّ خَمَّرْتَهُ وَلَوْ أَنْ تَعْرِضَ عَلَيْهِ عُودًا