“As the PCUS came into being, it sought to live by these principles [that is, regulative principle of worship articulated in the 108th and 109th questions and answers of the Westminster Larger Catechism] very strictly. That this is the case may be illustrated with regard to the matter of the Church calendar, and the observance of special days, such as, Christmas and Easter. The 58th question of the Shorter Catechism, commenting on the Fourth Commandment, says: ‘The fourth commandment requireth the keeping holy to God such set times as He hath appointed in His Word; expressly one whole day in seven, to be a holy Sabbath to Himself.’ The Assembly of 1899 was asked by an overture to make a ‘pronounced and explicit deliverance’ against the recognition of ‘Christmas and Easter as religious days.’ The following answer was given: ‘There is no warrant in Scripture for the observance of Christmas and Easter as holy days, rather the contrary (see Gal. 4:9-11; Col. 2:16-21), and such observance is contrary to the principles of the Reformed faith, condusive to will-worship, and not in harmony with the simplicity of the Gospel of Jesus Christ.’ Generally speaking, this would seem to exclude any church calendar other than the regular Sabbath days of the week.” — Morton H. Smith, How the Gold is Become Dim: The Decline of the Presbyterian Church, U.S. as Reflected in Its Assembly Actions (1973), pp. 98-99