Abu Ishaq (may Allah have mercy on him) says that al-Harith left a will that Sayyiduna Abdullah bin Yazid (may Allah be pleased with him) should lead his funeral prayer. Then he was placed into the grave from the foot end, and he said: "This is the Sunnah."
This chain is sahih (authentic). Since he said 'This is from the Sunnah', it has become like a musnad (Prophetic) report. We have also narrated this statement from Ibn Umar and Anas bin Malik.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الجنائز / 7052
Ibn Jurayj (may Allah have mercy on him) narrates from Imran bin Musa (may Allah have mercy on him) that the Messenger of Allah (peace and blessings be upon him) was lowered into the niche grave from the side of his head.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الجنائز / 7053
It is narrated from Sayyiduna Abdullah bin Abbas (may Allah be pleased with them both) that the Messenger of Allah (peace and blessings be upon him) was lowered into the niche grave from the side of his head.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الجنائز / 7054
Abu al-Zinad, Rabi'ah and Abu al-Nadr, all three without any disagreement among them, state that the Messenger of Allah (peace and blessings be upon him), Sayyiduna Abu Bakr and Sayyiduna Umar (may Allah be pleased with them both) were lowered into the niche grave from the side of the head. The Shaykh says: This practice is well known among the people of the Hijaz.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الجنائز / 7055
Ibn Buraydah narrates from his father (Sayyiduna Buraydah, may Allah be pleased with him) that the Prophet (peace and blessings be upon him) was brought into the grave from the direction of the qiblah, a niche grave (lahd) was dug for him, and bricks were set upright over it.
This Abu Burdah is Amr bin Yazid al-Tamimi al-Kufi, and he is da'if (weak) in hadith; Yahya bin Ma'in and others declared him weak.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الجنائز / 7056
Sayyiduna Abdullah bin Abbas (may Allah be pleased with them both) says that the Messenger of Allah (peace and blessings be upon him) entered a grave at night, and a lamp was lit for him (peace and blessings be upon him). He took him (the deceased) from the direction of the qiblah and said four takbirs, then said: "May Allah have mercy on you! You were indeed forbearing and a reciter of the Qur'an."
This chain is weak, and it has also been narrated through another weak route from Ibn Mas'ud. But what Imam al-Shafi'i (may Allah have mercy on him) mentioned is widespread in the land of the Hijaz; the later generations took this practice from the earlier ones, and it is more worthy of being followed.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الجنائز / 7057