Try reading the Bible as a process that occurred over approximately 4,000 years; taking people from the environment and state they were in and preparing them in a manner that they could comprehend to receive the gift of Christ’s passion and understand it. Any means of examining our environment, Christianity included, should not be used in isolation. If we try to understand the actions of God throughout the history purely from the perspective of our current understanding we take His actions out of the context in which they occurred. We use different methods to teach our children at each stage of their development. When they are infants we hold them, feed them and change their diapers to form a bond with them. As toddlers we never leave them unattended and we use physical acts to train them. As children we demand that they be obedient to our guidance, to accept what we tell them without questioning. As they mature we begin to reason with them and help them develop their own ethics. When they reach adulthood we offer them advice and assistance but leave them to determine their own actions. No one would spoon feed their normal, healthy 30 year old and no one would expect their infant to get a job. It is the same with salvation history. God acted in the way that would be understood within the context of civilization at that time.
I suggest that it is not reasonable to expect that God should have acted 3,000 years ago the same way we expect Him to act now; not because He has changed but because mankind has changed. The means of coaxing progress in a brutal, savage environment is different from the methods needed during an age of reason. As Christians, we hold that the truth has been revealed to us by a loving God, first through the faith of Abraham, next through his descendants who remained true to that faith, then through Jesus Christ and now through His Church. It is a process which has evolved and continues to evolve.