In Commonwealth v. Wolf (1817), the Supreme Court of Pennsylvania explained that “laws cannot be administered in any civilized government unless the people are taught to revere the sanctity of an oath. It is of the utmost moment, therefore, that they should be reminded of their religious duties,” thus again coupling an oath with a religious duty. Early school books also taught that to take any oath inherently required a belief in God. One text explained, “An oath supposes that he who takes it believes that there is a God who will in a future life reward the worthy and punish the wicked.” 58 An early House Judiciary Committee also declared: Laws will not have permanence or power without the sanction of religious sentiment without a firm belief that there is a Power above us that will reward our virtues and punish our vices.
In his arguments before the U. S. Supreme Court, Daniel Webster, the great “Defender of the Constitution,” queried: “What is an oath?” It is founded on a degree of consciousness that there is a Power above us that will reward our virtues or punishour vices. Our system of oaths in all our courts, by which we hold liberty and property and all our rights, are founded on or rest on Christianity and a religious belief.
He further noted: We all know that the doctrine of the law is that there must be in every person who enters court as a witness, be he Christian or Hindoo, there must be a firm conviction on his mind that falsehood or perjury will be punished either in this world or the next or he cannot be admitted as a witness. If he has not this belief, he is disfranchised [not admitted]. Justice Story confirms this, declaring that “infidels and pagans were banished from the halls of justice as unworthy of credit,” 62 and the New York Spectator of August 23, 1831, reported: The court of common pleas of Chester county New York a few days since rejected a witness who declared his disbelief in the existence of God.
The presiding judge remarked that he had not before been aware that there was a man living who did not believe in the existence of God; that this belief constituted the sanction of all testimony in a court of justice: and that he knew of no cause in a Christian country where a witness had been permitted to testify without such belief. This had long been the practice of courts. For example, Zephaniah Swift declared: All persons who believe in the existence of a God, let their religion be what it will, may be admitted to be witnesses. An oath is a solemn appeal to the Supreme Being that he who takes it will speak the truth, and an imprecation of His vengeance if he swears false.