Chesterton G.K. – Orthodoxy speaks to the truth and fundamental doctrines of Christianity as opposed to those who would compromise between the Devil and God.
Cox details the evidence for the doctrine of the Trinity in the Bible looking dozens of different angles.
In this very short 2 chapter work, Austin-Sparks (Deeper Life) presents us with the “horizoned by glory”. To be horizoned by something is to be completely overwhelmed by it.
Anon Basic Christian Doctrine is a 50 Chapter doctrines book that is anonymous.
Robert Shaw’s short 1 chapter work on God and the Holy Trinity is an excellent collection of observations and verses that defend the Trinity.
Henry Orton Wiley’s 3 vol Christian Theology work has 40+ chapters on the different areas of theology, such as, Bibliology, Theology Proper, etc.
A doctrinal book Body of Doctrinal Divinity is a set of 7 doctrinal books by Reformed John Gill.