It was the practice of the Prophet (peace and blessings be upon him):
"He (peace and blessings be upon him) would not eat while reclining, nor would two men walk behind him treading on his heels."
Hadith Referenceصحیح الجامع الصغیر / حرف الكاف / 4840
Hadith Gradingالألبانی:صحيح
Hadith Takhrij[حم] عن ابن عمرو. المشكاة ٤٢١٢، الصحيحة ٢١٠٤: د، ابن سعد.