Meditations 4.31.1
Marcus Aurelius to himself
Τὸ τεχνίον ὃ ἔμαθες φίλει, τούτῳ προσαναπαύου· τὸ δὲ ὑπόλοιπον τοῦ βίου διέξελθε ὡς θεοῖς μὲν ἐπιτετροφὼς τὰ σεαυτοῦ πάντα ἐξ ὅλης τῆς ψυχῆς, ἀνθρώπων δὲ μηδενὸς μήτε τύραννον μήτε δοῦλον σεαυτὸν καθιστάς.
Love the little craft you have learned, and find rest in it. Pass the rest of your life as someone who has entrusted all his affairs to the gods with his whole soul, making himself neither anyone's tyrant nor anyone's slave.