ἔργοισι χρηστός, οὐ λόγοις ἔφυν μόνον → a friend in deeds, and not in words alone
strong: Ar. and V. μεγασθενής, V. κραταιός, ὄβριμος, σθεναρός; see strong.
brave: P. and V. ἀνδρεῖς, V. εὔτολμος, Ar. and V. ἄλκιμος (rare P.); see brave.
trustworthy: P. and V. πιστός, φερέγγυος (Thuc. but rare P.).