Its often said that the God of the OT is different to the one in the NT. Even some Christians believe this and say that we don't need the former any longer, just the latter! The line of argument is that in the OT, God is very judgmental and severe in his ways and manner when dealing with people. However, in the NT he is truly a God of love and the harshness has now gone.

But this belief is not based on fact. Even a casual read of the Gospels shows that Jesus himself referred to hell and judgment a lot. We have to be careful that we don't develop an image of God that fits our own ideal. We do this by majoring on the parts of scripture that appeal to the image we have created of God, and ignoring the ones that don't.

In order to understand the NT fully, we need to have a comprehensive grasp of what the OT is about. The Book of Hebrews is a classic example of this, as it takes things such as the priesthood, the tabernacle, sacrifice etc and then develops them to apply to Christ and the NT. Rather than do away with the old, Hebrews shows how the new is a natural evolution and that there is no conflict between the Testaments, but rather a harmony.

People in the OT were saved in exactly the same way the ones in the NT are through Christ. The only difference is that in the former, it was the Messiah that was to come, whilst in the latter, it was the Messiah that had come. The fact remains that salvation is only through Christ. God's revelation on salvation was progressive. Moses knew more than Adam, Isaiah knew more than Moses did, Paul knew more than Isaiah.

There is a total unity between both Testaments. Matthew, for example, quotes seventy times from the OT. In fact a specific read of the books of the NT reveals just how strong the link is with the OT. The New does not do away with the Old, but rather the two compliment each other, as we see the progressive revelation of God.

Even when we see certain things cancelled by the NT, it is only because that they have found fulfillment in Christ. The animal sacrifice system is a good example. The reason why we don't do that any longer is because Jesus has become our sacrificial lamb. His blood does not merely cover our sins, but takes them away. There is still a total and complete harmony between the Testaments.

When we look at the Bible, rather than see it as two separate books, we should view it as one. Although the revelation of God is progressive as we read on, his character does not change but is constant.