Let Not Your Heart Be Troubled

Homer, Odyssey 13.362 (Athena to Odysseus; tr. A.T. Murray):

Be of good cheer, and let not these things distress thy heart.

θάρσει, μή τοι ταῦτα μετὰ φρεσὶ σῇσι μελόντων.

Also at Odyssey 24.357 (Odysseus to Laertes) and Iliad 18.463 (Hephaestus to Thetis). Cf. also Iliad 19.29 (Thetis to Achilles):

τέκνον, μή τοι ταῦτα μετὰ φρεσὶ σῇσι μελόντων.