Genre and place in the book. Three brief counsels for the "rest of life" (τὸ ὑπόλοιπον τοῦ βίου): (1) love your craft and rest in it; (2) entrust all to the gods with your whole soul; (3) be neither tyrant nor slave to anyone. A programme of a tranquil maturity — in the key of 04-30 and Med. 8.1.
Τὸ τεχνίον — "the craft you have learned." τεχνίον is a diminutive of τέχνη: a "humble art." Love it, rest in it (προσαναπαύου — "lean on, repose in"). What is meant is probably the art of living / the philosophy Marcus has learned (cf. 04-30 — holding to one's own without bookish luxury; the τέχνη of living — 04-02). Contentment with one's own, without envy of another's craft.
Entrust all to the gods. θεοῖς ἐπιτετροφὼς τὰ σεαυτοῦ πάντα ἐξ ὅλης τῆς ψυχῆς — having entrusted all his own things to the gods with his whole soul: a full trust in providence, not clinging to the outcome (DOGMAamor-fati; cf. Med. 8.1; the hymn 04-23). ("With his whole soul" here is the idiom of completeness, "without reserve.")
Neither tyrant nor slave. ἀνθρώπων μηδενὸς μήτε τύραννον μήτε δοῦλον — to lord it despotically over no one, and to cringe before no one. The Stoic freedom (ἐλευθερία) in relations: equality, without domination and without servility (cf. Epictetus, Disc. 4.1 "On freedom"; 01-14 — from Severus Marcus took the idea of a polity of equal law and the freedom of the governed). Especially weighty from one who could be a tyrant.
The disciplines. The principal one is desire: to entrust oneself to the gods, to be content with one's own. The secondary is action: freedom in relations — neither tyrant nor slave.
Parallels. To love and rest in one's art — 04-30; 04-02; cf. virtue-is-sufficient. To entrust all to the gods — Med. 8.1; 04-23; 10.21 (cf. DOGMAamor-fati). Neither tyrant nor slave — Epictetus Disc. 4.1; 01-14.