We are aware of that system of theology which regards the New Testament as furnishing the only code of laws by which men are bound since the death of Christ. We have looked at this doctrine with attention; and so far as the order, government, and ordinances of the _church_ are concerned, we admit its truth. As the laws and ordinances of the _Jewish_ church were determined by the _Old_ Testament, so the laws and ordinances of the _Christian_ church are determined solely by the _New_ Testament. Therefore, we should say at once, the argument is yours, if the Sabbath were a church ordinance. In such case, however, none but the church has a Sabbath. But the question is not concerning church ordinances. In these we follow the New Testament as closely as yourselves. The question is concerning an institution which has respect to mankind at large--to man _as_ man; for the Saviour teaches us that the Sabbath was made _for_ man. Now, it will be a very hard matter to prove, that when men as rational creatures are concerned, the only code of laws by which they are bound is the New Testament. Let us put the matter to the test. How will you prove that it is unlawful for a man to marry his sister, his daughter, or any other of near kin? The New Testament utters not a word on the subject. It is not enough to say, It is implied in the law which forbids adultery; for it must first be proved to be a species of adultery to do so. Nor will it do to say, The common sense of mankind is a sufficient law on the subject; for the moment we suppose that its unlawfulness is to be determined in this way, we abandon the argument that the New Testament is the only code of laws, and resort to the common sense of mankind as furnishing a part of the code. But if the common sense of mankind shall furnish a part of the code by which we are bound, who shall undertake to say how large a part? Besides, on this principle, the book of divine revelation is not complete and perfect. It is a lamp to our feet only in part, and the common sense of mankind makes out the deficiency! You are, therefore, driven to take your stand again upon the New Testament. Finding you there again, we repeat the question, _How do you prove by your code that a man may not marry his sister?_ It is impossible. You must, of necessity, look to that division of the Scriptures usually called the Old Testament; for the New says not one word about it.