Origen of Alexandria : It seems worthy indeed, after these things, to look at and perceive what God speaks to Israel himself through a vision, and how he sends him to Egypt, strengthening and exhorting him as one setting out to certain contests. For he says: "do not fear to go down into Egypt," that is to say: as you are about to engage "against principalities and powers and against the rulers of the darkness of this world" — which is figuratively called Egypt — do not fear, do not tremble. And if you also wish to know the reason why you ought not to fear, hear my promise: "for I will make you into a great nation there, and I will go down with you into Egypt, and I will call you back thence at the end." He does not, then, fear "to go down into Egypt," he does not fear the contests of this world and to undergo the struggles of the opposing demons, with whom God has gone down into the contests. In short, hear the Apostle Paul saying: "I labored more," he says, "than all of them, yet not I, but the grace of God with me." But also in Jerusalem, when the sedition had been stirred up against him and he was sweating out a most glorious contest for the word and preaching of the Lord, the Lord stood by him and said the same things which are now said to Israel: "do not fear," he says, "Paul, because, as you have testified concerning me at Jerusalem, so must you give testimony also at Rome." — HOMILIES ON Genesis 15.5