Sermons on Important Doctrines by John Colquhoun
John Colquhoun is one of the greatest Scottish Presbyterian preachers ever. Several of his books are classics ("Repentance," "Law and Gospel," and "Spiritual Comfort"). Here are sermons on the most essential doctrines of all: the Person and work of Christ, justification by faith alone, sanctification, salvation from sin, and others.
We can never study these non-negotiable matters enough.