Hadithcore
Riyad as-Salihin, 821

Ibn 'Umar (May Allah be pleased with them) reported:

I saw Messenger of Allah (ﷺ) sitting in the compound of the Holy Ka'bah, with the thighs against the stomach and arms around his legs. <b>[Al- Bukhari]</b>.

وعن ابن عمر رضى الله عنهما قال‏:‏ رأيت رسول الله صلى الله عليه وسلم بفناء الكعبة محتبياً بيديه هكذا‏.‏ ووصف بيديه الاحتباء، وهو القرفصاء‏.‏ ‏‏(‏‏(‏رواه البخاري‏)‏‏)‏.‏

References1 variant
In-Book Reference
Book 4, Hadith 9
Sharh · explanationclick to expand
<b>Guidance from the Hadiths:</b><br> 1) It is permissible to sit cross-legged or squatting. This gives people leeway in this respect.<br> 2) The appearance and attitude of the believers should make others hold them in awe. But why do our enemies not fear us? The reason for this weakness: our love for worldly life and hate of death. We ought to revive faith within the Ummah again!<br> 3) It is forbidden to sit like those with whom Allah Almighty is angry, with the hand behind the back and the palm on the ground, while resting on it.<br> Note:<br> The Shariah prohibits imitation of disbelieving nations in general, which includes those with whom Allah Almighty is angry, i.e. the Jews. This Muslim Ummah should be distinct in all things, even in the manner of sitting.