The Lioness And The Sheep

Ὥσπερ λεαίνῃ συννέμεσθαι πρόβατον ἡ φύσις οὐκ ἔδωκεν· οὕτως οὐδε τῦφον μοναχικῇ συνοικεῖν ὅλως ἐνδέχεται. Ὁ μὲν γὰρ θηριώδης ἐστὶ καὶ ἀκάθεκτος· ἡ δὲ πάντα εὐπειθῶς τὰ χρηστὰ καταδέχεαι, καὶ τὰ λυπηρὰ καρτερῶς μάλα προσίεται. Εἰ τοίνυν πρὸς ταύτην ἀπεδύσω γυμνάσασθαι, ἐκείνου ἀπόστηθι· μή τί σε δεινὸν διὰ τούτου ἐργάσηται, ὁ ἔναντι Κυρίου τραχηλιάσας, καὶ πάντας ἔχειν ζηλωτὰς τῆς οἰκείας ἐπάρσεως καὶ πτώσεως προθυμούμενος. Ἅγιος Ἰσίδωρος Του Πηλουσιώτου, Βιβλιον Πρῶτον, Ἐπιστολή ΤΞΗ’ Σευηρῳ Source: Migne PG 78.392a

As nature does not allow that a lioness and a sheep may feed together, likewise it is not possible for pride to dwell in the monastic life. For the former is fierce and will hardly be leashed, while the latter meekly receives all that is beneficial into its soul and bravely endures grievous trials. If, then, you have bound yourself with a zeal for imitation to the latter, withdraw from the former, lest that which raises its neck against the Lord do something terrible to you, that which desires that all be imitators of its pride and of its ruin. Saint Isidore of Pelusium, Book 1, Letter 368, to Severus