When you follow a bier, do not sit until it is placed on the (ground).
Sahih Muslim Book 11, Hadith 98
← Previous Hadith Should anyone amongst you see a bier he must stand up so long as it is within sight in case he does not intend to follow it.

Sahih Muslim Book 11, Hadith 97 Next Hadith → Whenever you come across a bier you should stand up, and he who follows it should not sit down till it is placed on the ground.

Sahih Muslim Book 11, Hadith 99