Saint Satan,
You are right when you say that the Bible is full of imperfect men. You should however do two things before you criticize them- one is to follow through on the complete story and two is to understand the teaching that is evident in the story. As for Abraham, the story is actually very beautiful and is an example of what God was willing to do when he sent Jesus to die for our sins. If you read it carefully you will see how heartbroken Abraham is at the notion that his only son, who he clearly loved very much, should be sacrificed. Issac, who also clearly loves his father obeys him willingly. And both of them, who love God know that he will provide for them, which he does. The story is one of a test of faith and devotion. It is not a story of human sacrifice and should not be portrayed as such.
As for David, he did do some horrible things beyond adultry. He sent the husband of his lover into battle to be killed so he could marry her. But the story doesn't end there. David had to pay for his sins and he had to confess them The story of David's life is one of a sinful man who loves the Lord and through his repentance and acknowledgement of his wrongdoing is used by God to do great things. He is an example to us all.
The problems thee people faced in their lifes as a result of their sinful behavior is not ignored. Far from ignoring them we can learn from them.They are examples of how sinful actions can cause sorrow, pain, and can destroy the family. Their lives prove the point I was making. A lifestyle like that that is attempted to be justified and glorified will only lead to pain and destruction. The men of the old testament who you mentioned saw the error of their ways and repented and their familes were better for it.
With all this said, how does their actions disprove that the morality taught by the Christian faith promotes the values I expressed earlier?
By the way, even if I was walking around with all of the physical infirmities that you mentioned, I would believe I was in a better situation than most if my faith was strong and I was a good moral person who cared for his spouse and his family.I would still be happy with myself. (Note I said better situation, not better)
God Bless