truth

Deut 32:4 Prov 3:5 Luke 24:44 John 20:29
A truth is something that has been proven. A lie is something that is not true. The Bible is full of many promised and proven truths. The Old Testament is full of God's promises that became reality. Whether it took a few hours or a few thousand years. It's easy to believe in a proven truth because you have the promise and the proof before you.
Sometimes we get caught up in things or situations and we believe something to be true when it isn't. The lie can be presented in such an alluring way that we want to believe it is a truth. This is the way Satan works. He is a liar, and will present his lies so well that they are "too good to be true". The enemy builds us up so high and tears us down so often that sometimes it becomes hard to trust anyone or anything.
I believe this is why there are so many names and details in the Old Testament. God is telling us "I am a truthful God!!". He establishes His honesty with us so that we can accept His unproven promises as truth. He keeps discloses everything so we don't find something out and wonder what else he is hiding.
It is sometimes hard to think of everything in the Bible as truth - especially if it hasn't been physically proven. But that's why God gives us faith. The belief that He is speaking the truth because He promised He would, and He backs up his reputation by showing us His track record.