51. If this discourse, in which I have supposed myself to have been teaching some uninstructed person in my presence, appears to you to be too long, you are at liberty to expound these matters with greater brevity. I do not think, however, that it ought to be longer than this. At the same time, much depends on what the case itself, as it goes on, may render advisable, and what the audience actually present shows itself not only to bear, but also to desire. When, however, rapid despatch is required, notice with what facility the whole matter admits of being explained. Suppose once more that some one comes before us who desires to be a Christian; and accordingly, suppose further that he has been interrogated, and that he has returned the answer which we have taken the former catechumen to have given; for, even should he decline to make this reply, it must at least be said that he ought to have given it;—then all that remains to be said to him should be put together in the following manner:—