The difference is, the Gardener's handbook can't be interpreted as God saying to kill all the Jews. Or all the Arabs. Or all the Muslims. Or all the blacks. The Bible can.
If you think that's some crazy, fringe belief, look at who is accepting
Hagee's endorsement. Someone who could become the primary policy maker in the country.
When you say you believe everything in the Bible, you are saying you believe:
1) That it's OK to own slaves, provided they are strangers or heathens. (Leviticus 25:44-46)
2) In committing genocide based on race (Samuel 15:2-3)
3) That God wants war (Exodus 15:3)
4) In committing genocide based on ethnicity as long as you spare the virgins.(Numbers 31)
5) In killing anyone who worships a different god or who worships differently. (Deuteronomy 13:6-16)
6) In killing disobedient children as prescribed by Old Testament law. (Mark 7:9)
7) In killing anyone who refuses to be ruled by Jesus. (Luke 19:22-27)
Saying you believe all those things is a lie.
If you really held all those beliefs you would be in jail right now for murdering just about everyone you met.