A young ungrounded Christian, when he sees all the fundamental truths, and sees good evidence and reasons of them, perhaps may be yet ignorant of the right order and place of every truth. It is a rare thing to have young professors to understand the necessary truths methodically: and this is a very great defect: for a great part of the usefulness and excellency of particular truths consisteth in the respect they have to one another. This therefore will be a very considerable part of your confirmation, and growth in your understandings, to see the body of the Christian doctrine, as it were, at one view, as the several parts of it are united in one perfect frame; and to know what aspect one point has upon another, and which are their due places. There is a great difference betwixt the sight of the several parts of a clock or watch, as they are disjointed and scattered abroad, and the seeing of them conjointed, and in use and motion. To see here a pin and there a wheel, and not know how to set them all together, nor ever see them in their due places, will give but little satisfaction. It is the frame and design of holy doctrine that must be known, and every part should be discerned as it has its particular use to that design, and as it is connected with the other parts.
Doctrine is useless if it is not accompanied by a holy life. It is worse than useless; it does positive harm. Something of "the image of Christ" must be seen and observed by others in our private life, and habits, and character, and doings.
Systematic theology is any study that answers the question, "What does the Bible teach us today?" about any given topic.Systematic Theology, 21 (John Frame cited)
On this subject men run into two extremes. Those who confound philosophy with theology err on the side of excess. This the false apostles formerly did who incorporated various unsound philosophical opinions with the Christian doctrine and are on this account rebuked by the apostle (Col. 2:8). Some of the fathers, coming out from among the philosophers, still retained some of their erroneous opinions and endeavored to bring the Gentiles over to Christianity by a mixture of philosophical and theological doctrines: as Justin Martyr, Origen, Clement of Alexandria, and the Scholastics, whose system is philosophical rather than theological since it depends more upon the reasonings of Aristotle and other philosophers than upon the testimonies of the prophets and apostles.
A religion without doctrine or dogma is a thing that many are fond of talking of in the present day. It sounds very fine at first. It looks very pretty at a distance. But the moment we sit down to examine and consider it, we shall find it a simple impossibility. We might as well talk of a body without bones and sinewsHoliness, Ch 4
The question becomes more pressing when we note that much of the best work on classical theism and Trinitarianism of the last thirty years has been done by Roman Catholic theologians. One thinks, for example, of the work of Brian Davies, Khaled Anatolios, Lewis Ayres, Gilles Emery, Thomas Weinandy and Matthew Levering. Evangelical work in the same field has tended to be less rigorous or, worse still, to deviate from classical orthodox notions of God and Trinity. Immutability, impassibility, and doctrines such as the eternal generation of the Son have been abandoned or reduced in importance by large sections of the evangelical world.http://reformedanglicans.blogspot.ca/2015/03/17-march-2015-ad-ecttale-of-two.html