“If you ask me,” says the Rev. Alexander Gordon, “what I should reckon Priestley’s greatest service to theological science, I should say that it is to be found in his adoption of the historical method of investigating the problems of doctrine and in his special handling of that method. The faith of Priestley was the precursor of the modern theme of theological development, though I do not think he used the term. His term was ‘corruption,’ a term which, it may be said, begs a very important question. At any rate it throws into strong relief the fact, on which all are agreed, that there is, and must be, some primitive nucleus whence developments proceed. Now it is the object of all who, for any reason, are interested in the origin of Christianity to reach this primitive nucleus at its first, undeveloped and uncorrupted stage. Where are we to seek it? By universal consent we must go to the New Testament. There, if anywhere, we shall come upon its traces. Here the agreement begins and ends. The New Testament is in all hands. But one man finds the Trinity in it; another the simplest Monotheism; a third, the papacy; a fourth, the supremacy of the illuminating spirit. The same words yield opposite results, because the principles of interpretation differ. The New Testament is to be interpreted by the voice of the Church; or by the testimony of the Creeds; or by the opinions of the Fathers of the first centuries before the age of dogmatic creeds began at Nicæa. These had been the expedients proposed by the Catholic, the Anglican, the Arian respectively. Socinus had rejected them all. It cannot matter to me (so, in effect, he contended) what any Church, or any Creed, or any Father may have said; I go to the New Testament myself, to read it with my own eyes, to understand it with my own mind. “This was not the position of Priestley. He thought this as irrational a proceeding as any of those which it superseded. Even if, by good luck, the true sense were reached, there was no means of proving it to be such. The New Testament, in Priestley’s view, is not to be construed as a book of enigmas which might belong to any age. It is not dropped straight out of heaven into the hands of the man of to-day for him to make what he will of it. It belongs to a specific period; it was written for a given class of persons; it was written to be understood. ‘Therefore,’ said Priestley, ‘it will be an unanswerable argument _a priori_ against any particular doctrine being contained in the Scriptures, that it was never understood to be so by those persons for whose immediate use the Scriptures were written, and who must have been much better qualified to understand them, in that respect at least, than we can pretend to be at the present day.’ (_Works_, vi. 7.)