It is narrated from Sayyiduna Abu Sa'id al-Khudri (may Allah be pleased with him) that he said: When the Prophet (peace and blessings be upon him) sat, he would raise his knees and wrap his hands around them (ihtiba'). (Allamah al-Haythami says:) I say: Abu Dawud recorded only this part: that he would wrap his hands around his knees (ihtiba').
Al-Bazzar recorded it; its chain contains Abdullah bin Ibrahim bin Abi Amrah al-Ghifari, who is da'if (weak).
Hadith Referenceمجمع الزوائد ومنبع الفوائد / كتاب الأدب / 12925