It is narrated from Sayyiduna Ibn Abbas (may Allah be pleased with them both) that the Noble Prophet (peace and blessings be upon him) said: "I have been commanded to prostrate on seven parts," (Wahib said, and he pointed with his hand to his nose), "and both knees, and the toes of both feet, and it was commanded that neither the clothes nor the hair be gathered."
Hadith Referenceسنن دارمي / من كتاب الصللاة / 1356
Hadith Takhrijیہ حدیث صحیح متفق علیہ ہے، دیکھئے: [بخاري 812] ، [مسلم 490]
Brief Explanation
(In explanation of Ahadith 1354 to 1356)
In the narration of Sahih Bukhari as well, the details of the seven limbs are as follows: the nose and forehead, both hands, the knees, and the toes of both feet. These make a total of seven limbs upon which prostration (sajdah) is obligatory. It is not correct to place only the forehead on the ground or to keep the toes of the feet raised above the ground; rather, their direction should be towards the ground facing the qiblah.