Pittheus
Πιτθεύς
The king who grasped the oracle Aegeus could not — and became Theseus's grandfather.
Son of Pelops and king of Troezen, famed as a sage of his age.
It was Pittheus who understood the oracle Aegeus brought back from Delphi — "do not loosen the wineskin's mouth before you reach Athens." Plutarch tells that he got his guest drunk and sent him to bed with his daughter Aethra.
He raised the grandson born of that night, Theseus, himself — and later his great-grandson Hippolytus grew up in his care too. Two generations of the Athenian royal house were raised in Troezen.
SourcesPlutarch, Life of Theseus