. The healing god could also
prevent disease and misfortune of all kinds: hence he is [Greek:
alexikakos] ("averter of evil") and [Greek: apotropaios]. Further, he is
able to purify the guilty and to cleanse from sin (here some refer the
epithet [Greek: iatromantis], in the sense of "physician of the soul").
Such a task can be fitly undertaken by Apollo, since he himself
underwent purification after slaying Python. According to the Delphic
legend, this took place in the laurel grove of Tempe, and after nine
years of penance the god returned, as was represented in the festival
called Stepterion or Septerion (see A. Mommsen, _Delphika_, 1878). Thus
the old law of blood for blood, which only perpetuated the crime from
generation to generation, gave way to the milder idea of the expiatory
power of atonement for murder (cf. the court called [Greek: to epi
Delphinio] at Athens, which retained jurisdiction in cases where
justifiable homicide was pleaded).

The same element of enthusiasm that affects the priestess of the oracle
at Delphi produces song and music. The close connexion between prophecy
and song is indicated in Homer (_Odyssey_, viii. 488), where Odysseus
suggests that the lay of the fall of Troy by Demodocus was inspired by
Apollo or the Muse. The metrical form of the oracular responses at
Delphi, the important part played by the paean and the Pythian nomos in
his ritual, contributed to make Apollo a god of song and music, friend
and leader of the Muses ([Greek: mousagetes]). He plays the lyre at the
banquets of the gods, and causes Marsyas to be flayed alive because he
had boasted of his superior skill in playing the flute, and the ears of
Midas to grow long because he had declared in favour of Pan, who
contended that the flute was a better instrument than Apollo's
favourite, the lyre.

A less important aspect of Apollo is that of a marine deity, due to the
spread of his cult to the Greek colonies and islands. As such, his
commonest name is _Delphinius_, the "dolphin god," in whose honour the
festival Delphinia was celebrated in Attica. This cult probably
originated in Crete, whence the god in the form of a dolphin led his
Cretan worshippers to the Delphian shore, where he bade them erect an
altar in his honour. He is _Epibaterius_ and _Apobaterius_ ("embarker"
and "disembarker"), _Nasiotas_ ("the islander"), _Euryalus_ ("god of the
broad sea"). Like Poseidon, he looks forth over his watery kingdom from
lofty cl