TIRMIDHI 2695:
from ʿAmr b. Shuʿayb from his father from his grandfather —
from his father, from his grandfather, that the Messenger of Allah ﷺ said: "He is not one of us who resembles other than us, no who resembles the Jews nor the Christians. For indeed greeting of the Jews is pointing the finger, and the greeting of the Christians is waving with the hand."
الترمذي ٢٦٩٥:
عن عمرو بن شعيب عن أبيه عن جده —
أَنَّ رَسُولَ اللَّهِ ﷺ قَالَ لَيْسَ مِنَّا مَنْ تَشَبَّهَ بِغَيْرِنَا لاَ تَشَبَّهُوا بِالْيَهُودِ وَلاَ بِالنَّصَارَى فَإِنَّ تَسْلِيمَ الْيَهُودِ الإِشَارَةُ بِالأَصَابِعِ وَتَسْلِيمَ النَّصَارَى الإِشَارَةُ بِالأَكُفِّ
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