Why Do We Live With Fear?

Today's Reading~Genesis 12-14; Luke 5
Okay so I'm about to go on a tirade so I apologize in advance. I read about Abram today and the first two promises God gave to him. The first was that God would make Abram's name great and bless the whole world through him. God's orders were for him to leave everything he knew. Abram obeys. God's second promise was that Abram's descendants would posses the land of Canaan. Cool! The famine hits and Abram leaves. I don't know about you, but if God promised my people some land I'm staying with the land, but that's just me. He goes to Egypt where he convinces Sarai to say she's his sister not his wife, and she does. Again, not what I would do, but okay the times were different. Here's my issue, why do we do it? Why do we receive promises from God and then live in fear? I realize it all works out for Abram and Sarai and I realize they learned lots of lessons, but is it in the human nature to live with fear? I see so much of it today. WE have so many phobias. We hesitate, we second-guess, we analyze, we over think. WHY?! Do we not have an awesome God? Is His promise not enough? If God says He will move on our behalf will He not keep His word? Okay, so we don't know how HE will do it, or how it will happen...do we really need to know? I am the first to stand in front of my accusing finger. I doubt God's promises, I hesitate, I second-guess, I over analyze, I over think, I am guilty. But I want to believe. I want to trust. I want to buy into God's promises even if I look a fool. And maybe that is the key. What if I buy into the promise and God lets me down? I'll look like I'm a fool. My only answer to myself is, what if God comes through and I have not trusted? Don't I look like a fool anyway? (Deep sigh) The rant is over, thanks for listening.