Plato, Laws 726a

ἀκούοι δὴ πᾶς ὅσπερ νυνδὴ τὰ περὶ θεῶν τε ἤκουε καὶ τῶν φίλων προπατόρων· πάντων γὰρ τῶν αὑτοῦ κτημάτων μετὰ θεοὺς ψυχὴ θειότατον, οἰκειότατον ὄν. τὰ δʼ αὑτοῦ διττὰ πάντʼ ἐστὶ πᾶσιν. τὰ μὲν οὖν κρείττω καὶ ἀμείνω δεσπόζοντα, τὰ δὲ ἥττω καὶ χείρω δοῦλα· τῶν οὖν αὑτοῦ τὰ δεσπόζοντα ἀεὶ προτιμητέον τῶν δουλευόντων. οὕτω δὴ τὴν αὑτοῦ ψυχὴν

Let everyone who has just heard the ordinances concerning gods and dear forefathers now give ear. Of all a man’s own belongings, the most divine is his soul, since it is most his own. A man’s own belongings are invariably twofold: the stronger and better are the ruling elements, the weaker and worse those that serve; wherefore of one’s own belongings one must honor those that rule above those that serve.