Now that is not quite as obvious as it sounds, because if you consider the typical approach to theology and to biblical matters over the past hundred years or so, you will find that almost invariably the starting point is with man. Everything associated with what is sometimes called modernism is always characterised by that; the theology is always subjective; it always starts with man himself. Because modernism is interested in itself, and in its so-called psychological ideas of origin, inevitably it starts either with man or with the world, and from that goes on to study the doctrine of God.
But that is not what the Bible says. The Bible starts with God; you remember its great opening statement which really tells us everything: ‘In the beginning God …’ It is very important that we should emphasise this and grasp it clearly. The knowledge of God is ultimately the sum of all other doctrines; there is no sense, there is no meaning or purpose, in any other doctrine apart from this great central, all-inclusive, doctrine of God Himself. There is no point in considering the doctrine of salvation, nor the doctrine of sin, unless we have started with the doctrine of God. But quite apart from such, more or less logical, considerations, we start with the doctrine of God because God is God, and because if we put anything or anybody before Him we are thereby dishonouring Him. We are failing to worship Him as we should and failing to conduct ourselves in His presence as the Bible teaches us to do.
David Martyn Lloyd-Jones, God the Father, God the Son (Wheaton, Ill.: Crossway Books, 1996), 47-48.