"Thou shalt not be afraid of them" (Deuteronomy 7:18). For Israel, "them" represented the massive, well-armed heathen nations they faced in the Promised Land. For us today, "them" represents every problem, trouble and overwhelming difficulty we face in life.
Why are we not to fear? Because God says so! No other explanation is needed. God is all powerful, all sufficient—and He is aware of the satanic strongholds we face. He knows every snare, trial and temptation that will ever be thrown at us. And He commands us, "You shall not fear any of them!"
Abraham was living in a strange country, surrounded by powerful kings, not knowing where he would end up. Yet God's first word to him was, "Fear not, Abram: I am thy shield, and thy exceeding great reward" (Genesis 15:1).
The meaning of this last phrase is, "I will be a wall around you, your protector, your defense." In essence, God was telling Abraham, "You are going to face difficulties but I will protect you through them all." Abraham responded by believing God's word to him: "He believed in the Lord; and he counted it to him for righteousness" (verse 6).
This same word came to Abraham's son, Isaac. He also lived in a hostile environment, surrounded by Philistines who hated him, harassed him and wanted him off their land. Scripture says that every time Isaac dug a well for a supply of water, the Philistines filled them back up: "The Philistines had stopped them, and filled them with earth" (26:15).
Everywhere Isaac went, he faced the same problem. He even called one well "Esek," which means "contention" (see 26:20). Apparently, Isaac felt nothing but contention in his life. He must have thought, "How will I ever feed my family and water my flocks? And how can I raise my children without fear, when the Philistines could plunder us at any time, with no problem? God, why have You planted me here? How can I ever make it?"
As this cloud of doubt formed over Isaac, God gave him the same word he gave Abraham: "I am the God of Abraham thy father: fear not, for I am with thee, and will bless thee, and multiply thy seed for my servant Abraham's sake" (verse 24).
We are children of Abraham and God makes the same promise to us he did to Abraham and his offspring: "If ye be Christ's, then are ye Abraham's seed, and heirs according to the promise" (Galatians 3:29).