My main approach to theology is biblical theology. In other words: I start with passages from the Christian Bible and move from those texts into descriptions of the things I’m studying, the things I see there.
About the Bible, in case you don’t know: the Christian Bible is usually divided up into two parts, the Old Testament and the New Testament.
The Old Testament is the story of Abraham and his family, the Jews. Four thousand years ago, God made a covenant with Abraham. In that covenant, God promised that he would belong to Abraham, bind himself to Abraham, for better and for worse. He would be Abraham’s God, and Abraham would be his man.
God promised to bless Abraham, and by blessing Abraham he would bless the whole world. Christians understand the ultimate fulfillment of this promise to be Jesus, the “Son of David, Son of Abraham,” as the Gospel of Matthew calls him (Matthew 1.1 and 1.17).
The New Testament is the story of Jesus and his followers, the Church. Two thousand years ago, God the creator entered his creation and became a human being, in the person of Jesus of Nazareth. He lived a life of perfect love and servanthood. He taught people a completely new way to relate to God, to themselves, and to each other.
Because he threatened their power base, and exposed their hypocrisy, the Jewish religious leaders had him arrested and executed by the Romans. But because he was God in the flesh, and to seal God’s victory over human rebellion and its consequences, God raised him from the dead.
After his resurrection, he empowered his followers to spread his teachings about how to relate to God, to themselves, and to each other. At its best, that’s what the Church is. That’s what Christianity is supposed to be.