This is what the battle was all about -- rescuing the body of Troilus, Hector's brother. Note that the Greek's did not hesitate to write right to left -- the orthodoxy of left to right came later. Many inscriptions are written with alternating lines going L->R and R->L (boustrophedon or like the turning of the cattle in plowing fields). Thus the dead hero's name reads (note that the Greek letter "r" {rho} is shaped like a p and here is turned backwards with the rest of the letters).

The story of Troilus' death is not told in the Iliad. Homer only mentions that he is dead. Later sources told that Achilles ambushed Troilus and his sister as they left the city to draw water. Achilles chased Troilus into the temple of Apollo and killed him there. It is generally consider bad to fight, let alone kill someone, in a temple or sacred precinct or at an altar. That violates all sorts of religious taboos. Apollo, in part as retribution for this desecration of his temple, later had a hand in Achilles' demise. The artist depicts the sacred nature of the location of the slaughter by depicting a bomos or altar, behind which Troilus has fallen. The concept that religious buildings confer "sanctuary" exists also in Christian religion. Victor Hugo's novel, the Hunchback of Notre Dame, provides a famous literary example of this. In modern America, there was a large sanctuary movement for Central American (esp. El Salvadorian) refugees. The legality of sanctuary is still largely debated in the U.S.