"...and to become myself a learner before I could attempt to teach; and upon such points as these it would be the very reverse of wisdom to dogmatize.""James Bannerman's 'The Church of Christ' is the most extensive, standard, solid, Reformed treatment of the doctrine of the church that has ever been written. It is indisputably the classic in its field. Every minister and elder should own a copy, and church members would also be much better informed if they perused it carefully. How many church problems would be alleviated if churches used Bannerman as their primary textbook for their understanding of what the church is and for their modus operandi! --Joel R. Beeke
Volume One of this two volume work (full title: The Church of Christ: a treatise on the nature, powers, ordinances, discipline, and government of the Christian Church) deals with the nature and power of the Church, containing a lengthy explanation of the Church in its relation to the state, which is arguably one of the best treatments of this topic available. From there it deals with matters in regard to which Church power is exercised (i.e. in regard to doctrine, ordinances, the instrumentality and time of public worship; with a discussion of holy days, Independency, and confessions). Volume Two continues where Volume One left off, providing a lengthy section on the sacraments, covering the parties in whom the right to exercise church power is vested, examining crucial points concerning Christian liberty, comparing the Popish, Prelatic, Independent, Congregational and Presbyterian systems, etc. Nine appendices deal with a wide range of practical topics including union between churches, Church/State relations, ordination, and valuable notes on the literature related to this subject.
Iain Murray, a prominent scholar and co-founder of the Reformed publishing house, The Banner of Truth Trust, has said of The Church of Christ that "for those who wish to study the doctrine of the Church in its several aspects as it was held by the majority of the Reformers, Puritans, Covenanters and leaders of 'The Third Reformation,' it will prove an invaluable textbook."
Here is part of the author's introduction.
It was with no ordinary feelings of doubt and distrust in my own powers, that I first set myself to cope with this high argument. With that measure of ability which God has given me, and which the Church has called upon me to exercise in the Chair in this College to which the Doctrine of the Church belongs, I have endeavoured to open up the general principles of a subject, almost entirely new in academic prelections, and especially arduous.If you are a pastor or teacher, do not assume that you have cornered the market or have a full and complete grasp on this subject. It is so important, when using the term "Church" from the pulpit or during a bible study, that you clearly define which "church" you are referring to when you are quoting passages or making dogmatic statements, i.e. local, universal, invisible, etc. Your listeners will assume certain things and in most cases their assumptions will be incorrect. As lay person who engages in conversations after a teaching on "the church"; I can guarantee you that the people are confused. In fact, there is always the possibility that some of you may be confused, as well.
I have found the task to be one beset with difficulties neither few nor small. Not the least of these has been the entire absence of any adequate guide--or often of any guide at all--to aid me in shaping my course and forming my opinions with respect to many of the most difficult and delicate questions connected with my subject. I have been compelled to take up these opinions very much at my own hand, and to become myself a learner before I could attempt to teach ; and upon such points as these it would be the very reverse of wisdom to dogmatize.
I shall be more than rewarded for the time and labour spent upon this great and arduous subject, if I have been enabled, in however small a measure, to impart some knowledge of the truths, or to suggest some of the grand principles, or even to awaken some interest in the argument of a department in theology, a thorough acquaintance with which is so essential for those who hope to occupy, or who already fill, that honourable yet responsible place, held by those who are put in trust with the work of the ministry in the Church of the Lord Jesus Christ.
If you are responsible for teaching others in any leadership capacity; I strongly recommend this 2 volume set. You can read it online here: http://ia700300.us.archive.org/4/items/churchofchristtr01bann/churchofchristtr01bann_djvu.txt