The 1689 London Baptist Confession of Faith in Modern English by Founder's Press. The Westminster Confession of Faith, as ingenious as it was, was a rough outline for the doctrinal refinement that would follow, and I have found no document or confessional statement to be more refined doctrinally than the 1689 confession. If you want to know what I believe, read this confession. I affirm the confession because I cannot refute any of it's key doctrines from the Bible alone. Even the first section is a masterclass summary of Biblical doctrine:

1:1 The Holy Scriptures are the only sufficient, certain, and infallible standard of all saving knowledge, faith, and obedience.1 The light of nature and the works of creation and providence so clearly demonstrate the goodness, wisdom, and power of God that people are left without excuse; however, these demonstrations are not sufficient to give the knowledge of God and His will that is necessary for salvation.2 Therefore, the Lord was pleased at different times and in various ways to reveal Himself and to declare His will to His church.3 To preserve and propagate the truth better and to establish and comfort the church with greater certainty against the corruption of the flesh and the malice of Satan and the world, the Lord put this revelation completely in writing. Therefore, the Holy Scriptures are absolutely necessary, because God’s former ways of revealing His will to His people have now ceased.4
Five Lies of our Anti-Christian Age by Rosaria Butterfield.

Here are the five lies:
Lie #1: Homosexuality is normal.
Lie #2: Being a "spiritual" person is kinder than being a Christian.
Lie #3: Feminism is good for the world and for the Church.
Lie #4: Transgenderism is normal.
Lie #5: Modesty is an outdated burden that serves male dominance and holds women back.

Butterfield was once a lesbian but upon learning of the Gospel and placing her faith in Christ, she has repented of her sin of homosexuality and is now a married housewife. She argues that your sexual "orientation" is not definitional of who you are as a person. Rather, whether God created you to be a man or a woman is definitional to your identity. If you are a man and experiencing lust for other men, that is sin corrupting your basic human nature. Homosexuality is not immutable or unchangeable. It can and must be repented of.
The Sovereign Grace of God by James R. White. This is White's exploration of the doctrines of Calvinism, to demonstrate that they are Biblical. Of course, I am not impartial, I am convinced that they are. The key doctrines of Calvinism being summed up in a 5-point system called TULIP (Total Depravity/Inability, Unconditional Election, Limited/Particular Atonement, Irresistible Grace, Perseverance/Preservation of the Saints). I did a mock up of an inverted TULIP, a system that would say the opposite of each point. For example, if Total Inability is false, does that mean Total Ability is true? Is man really able to do whatever he pleases? The Scriptures seem clear to me that he can't, but people will insist what they will.

Commentary on Galatians by Martin Luther. Out of all of Luther's commentaries this is the one to read. It also happened to be Luther's favorite and the best summation of his theology. It is historically significant to Protestantism as a whole.