George Gillespie, A Dispute Against the English Popish Ceremonies (Naphtali Press, 1993). The below is from sections online on the subject of holy days.
English Popish Ceremonies (Against Holy Days) | Naphtali Press Part 1: Holy Days take away our Christian Liberty Proved Out of the Law (EPC 1.7 31-36) | Naphtali PressThe Bishop has yet a third dart to throw at us: If the church (he says)7 has power, upon occasional motives, to appoint occasional fasts or festivities, may not she, for constant and eternal blessings, which do infinitely excel all occasional benefits, appoint ordinary times of commemoration or thanksgiving? ANSWER. There are two reasons for which the church may and should appoint fasts or festivities upon occasional motives, and neither of them agrees with ordinary festivities. 1. Extraordinary fasts, either for obtaining some great blessing, or averting some great judgment, are necessary means to be used in such cases; likewise, extraordinary festivities are necessary testifications [testimonies] of our thankfulness for the benefits which we have impetrate [procured] by our extraordinary fasts; but ordinary festivities, for constant and eternal blessings, have no necessary use. The celebration of set anniversary days is no necessary mean for conserving the commemoration of the benefits of redemption, because we have occasion, not only every Sabbath day, but every other day, to call to mind these benefits, either in hearing, or reading, or meditating upon God’s word. I esteem and judge that the days consecrated to Christ must be lifted, says Danæus: Christ is born, is circumcised, dies, rises again for us every day in the preaching of the Gospel.8
2. God has given his church a general precept for extraordinary fasts (Joel 1:14; 2:15), as likewise for extraordinary festivities to praise God, and to give him thanks in the public assembly of his people, upon the occasional motive of some great benefit which, by the means of our fasting and praying, we have obtained (Zech. 8:19 with 7:3). If it is said that there is a general command for set festivities, because there is a command for preaching and hearing the word, and for praising God for his benefits; and there is no precept for particular fasts more than for particular festivities, I answer: Albeit there is a command for preaching and hearing the word, and for praising God for his benefits, yet is there no command (no, not in the most general generality) for annexing these exercises of religion to set anniversary days more than to other days; whereas it is plain that there is a general command for fasting and humiliation at some times more than at other times.
7. Ib. p. 26, 27 [i.e. Pro. in Perth Assem., part 3, p. 13).
8. Apud. Bald., de Cas. Consc., lib. 2, cap. 12, cas. 1. Dies Christo dicatos tollendos existimo judicoque, says Danæus: quotidie nobis in evangelii prædicatione nascitur, circumciditur, moritur, resurgit Christus.
This is why Gillespie and the Westminster Assembly of divines classed occasions for fastings and thanksgivings as part of the special (occasional vs. regular) worship of God (WCF 21.5). The distinction between these valid and authorized aspects of public worship and the imposed holy days against which Presbyterians and Puritans contended is common Presbyterian doctrine, as a quote from Southern Presbyterian, William S. Plumer makes clear (William S. Plumer,
The Law of God, As Contained in the Ten Commandments [Philadelphia, 1864]):
Even days of fasting or thanksgiving are not holy days; but they are a part of secular time voluntarily devoted to God’s service. And if we are to perform these things at all, we must take some time for them. Yet none but God can sanctify a day so as to make it holy. The attempt to do this was one of the sins of Jeroboam, 1 Kings 12:33.
See also,
The Religious Observance of Christmas and ‘Holy Days’ in American Presbyterianism | Naphtali Press