ἤϊος
From LSJ
ἔνδον σκάπτε, ἔνδον ἡ πηγὴ τοῦ ἀγαθοῦ καὶ ἀεὶ ἀναβλύειν δυναμένη, ἐὰν ἀεὶ σκάπτῃς → Dig within. Within is the wellspring of Good; and it is always ready to bubble up, if you just dig | Look within. Within is the fountain of the good, and it will ever bubble up, if thou wilt ever dig.
English (LSJ)
ὁ, epith. of Phoebus,
A ἤϊε Φοῖβε Il.15.365, 20.152, h.Ap.120. (Prob. from the cry ἤ, ἤ, cf. ἰήϊος.)
