We might fancy God, at the beginning of all things, speaking His will concerning right and wrong, in the presence of the myriads of souls that lay in the state of possibility. And when, in the course of time, these souls come into being, with unfailing regularity, at every act, conscience, like a spiritual phonograph, gives back His accents and reechoes: "it is lawful," or "it is not lawful." Or, to use another simile, conscience is the compass by which we steer aright our moral lives towards the haven of our souls' destination in eternity. But just as behind the mariner's compass is the great unseen power, called attraction, under whose influence the needle points to the star; so does the will or Law of God control the action of the conscience, and direct it faithfully towards what is good. We have seen that, in order to prevaricate it is not sufficient to transgress the Law of God: we must know; conscience makes us know. It is only when we go counter to its dictates that we are constituted evil-doers. And at the bar of God's justice, it is on the testimony of conscience that sentence will be passed. Her voice will be that of a witness present at every deed, good or evil, of our lives. Conscience should always tell the truth, and tell it with certainty. Practically, this is not always the case. We are sometimes certain that a thing is right when it is really wrong. There are therefore two kinds of conscience: a true and a certain conscience, and they are far from being one and the same thing. A true conscience speaks the truth, that is, tells us what is truly right and truly wrong. It is a genuine echo of the voice of God. A certain conscience, whether it speaks the truth or not, speaks with assurance, without a suspicion of error, and its voice carries conviction. When we act in accordance with the first, we are right; we may know it, doubt it or think it probable, but we are right in fact. When we obey the latter, we know, we are sure that we are right, but it is possible that we be in error. A true conscience, therefore, may be certain or uncertain; a certain conscience may be true or erroneous. A true conscience is not the rule of morality. It must be certain. It is not necessary that it be true, although this is always to be desired, and in the normal state of things should be the case. But true or false, it must be certain. The reason is obvious. God judges us according as we do good or evil. Our merit or demerit is dependent upon our responsibility. We are responsible only for the good or evil we know we do. Knowledge and certainty come from a certain conscience, and yet not from a true conscience which may be doubtful.