One major misconception some people have with The Bible is that it preaches human sacrifice when this is untrue. God actually called such practices DISGUSTING:
Jer 32.35: They built high places for Baal in the Valley of Ben Hinnom to sacrifice their sons and daughters to Molech, though I never commanded, nor did it enter my mind, that they should do such a DETESTABLE thing and so make Judah sin.
Jer 7.31: They have built the high places of Topheth in the Valley of Ben Hinnom to burn their sons and daughters in the fire -- something I did not command, nor did it enter my mind.
Deut 12.31: You MUST NOT worship the LORD your God in their way, because in worshipping their gods, they do all kinds of detestable things the LORD hates. They even burn their sons and daughters in the fire as sacrifices to their gods.
One might bring up Abraham's test as God wanting human sacrifices but the test of Abraham was simply that: A test. Abraham needed to be tested to see if he would sacrifice his son to God to show that he would be willing to give up the thing he loved most. This would be in accordance to his duty as God's servant. God needed to see if Abraham was fully dedicated to his duty and that he was willing to sacrifice anything for him. When God saw that Abraham was going to sacrifice his son to him, he stopped him proving that he didn't want a human sacrifice at that it was only a test which Abraham passed. God also blessed Abraham and his descendants and then sacrificed his own son for humanity's salvation. The sacrifice of Jesus for humanity's sins was surely planned back then because of this.
Concerning the sacrifice of Jesus, Jesus was given choice. Jesus didn't have to sacrifice himself. God gave him the will to choose. Jesus chose to sacrifice himself.
John 10.17: The reason my Father loves me is that I lay down my life -- only to take it up again. No one takes it from me, but I lay it down of my own accord. I have authority to lay it down and authority to take it up again. This command I received from my Father.
Another major misconception that some people have with The Bible is that is mentions unicorns. They cite Job 39:9-12 for this. This is true but the unicorns it does mention aren't the unicorns from fairy tales and look nothing like them. One can even observe such creatures today. Further more, the use of unicorn was only used in later translations. The early translations don't mention unicorns. The King James Version for example replaces Re'em with unicorn. Re'em in Hebrew is ראם which means Oryx which other versions of The Bible have in replace to Re'em. Other versions call the Re'em a wild ox. So The Bible mentioning unicorns was an error on the translator's part because other older versions (and new ones have taken this on too) don't mention unicorns and Re'em doesn't mean unicorn. Further more, unicorns did exist once. Unicorn means "one horned" and the elasmotherium (an extinct species of the rhino) had ONE HORN on its head which technically makes it one horned and thus a unicorn. The Indian Rhinoceroses have the scientific name of Rhinoceros Unicornis because of them having one horn (although not on their head). Also, Marco Polo met an elasmotherium and called it a unicorn.
The most common misconception some people have about The Bible is that the earth is flat. They cite Revelation 7:1 as support for this major misconception but they forget that Revelation is completely symbolic and in reference to the future. It's not meant to be taken literally although some of the things are literal such as the return of Jesus and defeat of Satan. Isaiah 40:21-22 calls the earth a circle.
Luke 17:31 gives a complete allusion to day and night occurring simultaneously with day on one half and night on the other. This wouldn't be possible on a flat earth.
So there you have it. Three major misconceptions about The Bible debunked.