Sunan an-Nasa'i, Volume 6, Book 51, Hadith 5709 (DarusSalam) ⓘ
It was narrated from Yahya bin Sa'eed who heard Sa'eed bin Al-Musayyab say: "Thaqif welcomed 'Umar with a drink. He called for it, but when he brought it close to his mouth, he did not like it. He called for water to weaken it, and said: 'Do like this.'"
أَخْبَرَنَا زَكَرِيَّا بْنُ يَحْيَى، قَالَ حَدَّثَنَا عَبْدُ الأَعْلَى، قَالَ حَدَّثَنَا سُفْيَانُ، عَنْ يَحْيَى بْنِ سَعِيدٍ، سَمِعَ سَعِيدَ بْنَ الْمُسَيَّبِ، يَقُولُ تَلَقَّتْ ثَقِيفٌ عُمَرَ بِشَرَابٍ فَدَعَا بِهِ فَلَمَّا قَرَّبَهُ إِلَى فِيهِ كَرِهَهُ فَدَعَا بِهِ فَكَسَرَهُ بِالْمَاءِ فَقَالَ هَكَذَا فَافْعَلُوا .
also referenced under: Hadith 5706 (Reference) & Book 51, Hadith 168 (In-Book)