He was justifiable in doing so.
"If one should insist that there can be no intrinsic wrong in holding a fellow-being as property because God allowed Hebrews to sell themselves, and in certain cases to be servants forever, and directed the Israelites to buy servants of the heathen round about them, who should be an inheritance to the children of the Israelites, he would simply say either that the whole pentateuch which contained such a libel on the divine character, is thereby proved to be a forgery, or, that if the pentateuch is to be received, it only proves that in condescension to a race of freebooters who were employed, as the Israelites were, in bloody wars of extermination, slavery was allowed them, to prevent, perhaps, worse evils, and in consistency with their dark-minded, semi-barbarous condition.

In this enlightened age when Greece and Rome had shed superior light on human relationships and obligations, and especially since Christ had promulgated the golden rule, the idea that man could own a fellow-creature was so preposterous that he would be an infidel, nay, he would go farther, he would be an atheist, rather than believe it.

Our moral instincts are our guide.

They are the highest source of evidence that there is a God, and they are a perfect indication as to what God and his requirements should be.

He was for passing a vote of disapprobation at the act of Paul the Apostle in sending back Onesimus into bondage.