1 Timothy 3:15 ...that thou mayest know how thou oughtest to behave thyself in the house of God, which is the church of the living God, the pillar and ground of the truth.
Ephesians 3:10 To the intent that now unto the principalities and powers in heavenly places might be known by the church the manifold wisdom of God,
Concerning a Calling to the Ministry, and Clearness Therein
by: James Durham (1622-1658)
From: A Commentary Upon the Book of the Revelation, Revelation 1:19-20, Lecture IX pages 66-83 (of 60-83)
The Deacon: (offsite) An Inquiry into the Nature, Duties, and Exercise of the Office of Deacon, in the Christian Church.
by James M. Willson, A.M.
An Inquiry Into Principles Of Church Fellowship. (offsite)
by Rev. John T. Pressly, D.D.
Solemn Testimony Against Toleration
by the Commissioners of the General Assembly of the Kirk of Scotland. With the Answer of Parliament. 
A Sermon Against "Occasional Hearing"
by Rev. John Anderson
Biblical Worship (offsite)
by Kevin Reed
"The present ecclesiastical scene illustrates the urgency of seeking a biblical understanding of worship. Some churches are introducing "contemporary" modes of worship: drama, sacred dance, multi-media productions ? even puppet shows. Others advocate free-style services, wherein anyone present may exercise his "gifts" spontaneously ? religious democracy with a vengeance. There are still others who are alarmed by growing ecclesiastical anarchy; their solution is to embrace the liturgical forms of Rome, Canterbury, or Eastern Orthodoxy.
We hold a different perspective. We maintain that the Bible contains general principles which regulate all matters of worship. First, religious worship must be directed to the Lord God alone; worship must not be given to false deities, humans, or any created thing. Second, the only acceptable means of worship are those established by God." [from the Introduction]
I. The light of nature shows that there is a God, who has lordship and sovereignty over all, is good, and does good unto all, and is therefore to be feared, loved, praised, called upon, trusted in, and served, with all the heart, and with all the soul, and with all the might.  But the acceptable way of worshipping the true God is instituted by Himself, and so limited by His own revealed will, that He may not be worshipped according to the imaginations and devices of men, or the suggestions of Satan, under any visible representation, or any other way not prescribed in the holy Scripture. 
Why Do Presbyterians Observe Holy Days? (Offsite on PCANews) - "Puritans desired that only those elements directly instituted by God were present in their worship."
By Andrew Webb
Celebrating a Calvinist Christmas with a Clear Conscience: Is the Holiday Unpresbyterian? (offsite)
by: Mark Horne
A fresh article from the "pro-Christmas" point of view.
The Religious Observance of Christmas and 'Holy Days' in American Presbyterianism. (PDF offsite)
by: Chris Coldwell
While not written as a polemic piece per se it certainly has in view and was initially sparked by several of the strange ideas expressed in Mark Horne's 'Celebrating a Calvinistic Christmas with a Clear Conscience.' As such I'd appreciate it if you'd consider adding a link to the article from the Ecclesiology section at Reformed.org. –C. C.
Is Christmas Scriptural? (offsite)
by: G. I. Williamson
The Regulative Principle of Worship and Christmas (offsite)
by: Brian Schwertley
Agree or disagree? - This is an excellent treatment of the subject from a naysayers point of view.
Holy Days of Men and Holy Days of God (offsite)
by G. I. Williamson
Xmas (PDF offsite)
by A. W. Pink
All I Really Need to Know About Worship
(I Don't Learn from the Regulative Principle) (offsite at Chalcedon)
by Steve M. Schlissel
This is a must read series of articles (in progress) that asks some very pointed questions about the legitimacy of the Regulative Principle, and offers some solutions Rev. Schlissel calls, "The Informed Principle of Worship." Whether you are persuaded or not, this series is thought provoking and is igniting a fresh, and to the author, frustrating volley of new debate on this important subject.
• A Critique of Steve Schlissel's Article 'All I Really Need...' (PDF offsite at Blue Banner)
by G. I. Williamson
• A Brief Critique of Steven M. Schlissel's Articles Against the Regulative Principle of Worship (offsite)
by Brian Schwertley
Several resources that expound the Puritan, or American theory of the Christian Sabbath.-- The doctrine taught in the Westminster Standards.
Fisher's Catechism on the Fourth Commandment.
Q58: What is required in the Fourth Commandment?
Q59: Which day of the seven hath God appointed to be the weekly Sabbath?
Q60: How is the Sabbath to be sanctified?
Q61: What is forbidden in the Fourth Commandment?
Q62: What are the reasons annexed to the Fourth Commandment?
The Lord's Day (Offsite)
by Archibald Alexander
The Westminster Presbyterian (offsite)
Has resourses by: Thomas Boston, Jonathan Edwards, John Witherspoon, Charles Hodge, Robert Murray M'Cheyne, Jesse Johnson, William Young, John W. Keddie, James MacGregor (1830-1894), John Murray, G. I. Williamson, Sherman Isbell
Is Church Membership Optional? (offsite)
By: Stephen Pribble
Choosing a Church (offsite)
By: Stephen Pribble
Faithful Witness-Bearing Exemplified - A preface concerning association, toleration, and what is now called liberty of conscience.
by john howie of lochgoin [published 1783]
 ROM 1:20 For the invisible things of him from the creation of the world are clearly seen, being understood by the things that are made, even his eternal power and Godhead; so that they are without excuse.
Acts 17:24 God that made the world and all things therein, seeing that he is Lord of heaven and earth, dwelleth not in temples made with hands.
Psalms119:68 Thou art good, and doest good; teach me thy statutes.
JER 10:7 Who would not fear thee, O King of nations? for to thee doth it appertain: forasmuch as among all the wise men of the nations, and in all their kingdoms, there is none like unto thee.
Psalms 31:23 O love the Lord, all ye his saints: for the Lord preserveth the faithful, and plentifully rewardeth the proud doer.
PSA 18:3 I will call upon the Lord, who is worthy to be praised: so shall I be saved from mine enemies.
Romans 10:12 For there is no difference between the Jew and the Greek: for the same Lord over all is rich unto all that call upon him. PSA 62:8 Trust in him at all times; ye people, pour out your heart before him: God is a refuge for us. Selah.
JOS 24:14 Now therefore fear the Lord, and serve him in sincerity and in truth: and put away the gods which your fathers served on the other side of the flood, and in Egypt; and serve ye the Lord.
Mark 12:33 And to love him with all the heart, and with all the understanding, and with all the soul, and with all the strength, and to love his neighbour as himself, is more than all whole burnt offerings and sacrifices.
 DEU 12:32 What thing soever I command you, observe to do it: thou shalt not add thereto, nor diminish from it.
Matthew 15:9 But in vain they do worship me, teaching for doctrines the commandments of men.
Acts 17:25 Neither is worshipped with men's hands, as though he needed any thing, seeing he giveth to all life, and breath, and all things.
Matthew 4:9 And saith unto him, All these things will I give thee, if thou wilt fall down and worship me. 10 Then saith Jesus unto him, Get thee hence, Satan: for it is written, Thou shalt worship the Lord thy God, and him only shalt thou serve. (see also DEU 15:-19)
EXO 20:4 Thou shalt not make unto thee any graven image, or any likeness of any thing that is in heaven above, or that is in the earth beneath, or that is in the water under the earth: 5 Thou shalt not bow down thyself to them, nor serve them: for I the Lord thy God am a jealous God, visiting the iniquity of the fathers upon the children unto the third and fourth generation of them that hate me; 6 And shewing mercy unto thousands of them that love me, and keep my commandments.