But this question, of the moral relations which the consumers of slave labor products sustain to slavery, is one of too important a nature to be passed over without a closer examination; and, beside, it is involved in less obscurity than the morality of the relation existing between the master and the slave. Its consideration, too, affords an opportunity of discriminating between the different opinions entertained on the broad question of the morality of the institution, and enables us to judge of the consistency and conscientiousness of every man, by the standard which he himself adopts. The prevalent opinions, as to the morality of the institution of slavery, in the United States, may be classified under three heads: 1. That it is justified by Scripture example and precept. 2. That it is a great civil and social evil, resulting from ignorance and degradation, like despotic systems of government, and may be tolerated until its subjects are sufficiently enlightened to render it safe to grant them equal rights. 3. That it is _malum in se_, like robbery and murder, and can not be sustained, for a moment, without sin; and, like sin, should be immediately abandoned. Those who consider slavery sanctioned by the Bible, conceive that they can, consistently with their creed, not only hold slaves, and use the products of slave labor, without doing violence to their consciences, but may adopt measures to perpetuate the system. Those who consider slavery merely a great civil and social evil, a despotism that may engender oppression, or may not, are of opinion that they may purchase and use its products, or interchange their own for those of the slaveholder, as free governments hold commercial and diplomatic intercourse with despotic ones, without being responsible for the moral evils connected with the system, But the position of those who believe slavery _malum in se_, like the slave trade, robbery and murder, is a very different one from either of the other classes, as it regards the purchase and use of slave labor products. Let us illustrate this by a case in point.