Honestly, I think it’s my duty as a Christian to study Christian theology, to know the claims I claim to adhere to and how they were developed.
One example I can give you relates to a topic I’m sure I’ve repeated (and will again) throughout various threads in the forum – theology of two kingdoms. It’s one I may not live long enough to study fully enough, but was formalized by Augustine in his doorstopper City of God (which I have NOT read). Calvin and Luther (among many others) relied on Augustine’s work and developed (or maybe more accurately applied it) in their own contexts. Luther’s relatively brief treatment of it can be found here. I found it particularly helpful at the beginning of lockdowns in 2020.
The theology of Two Kingdoms examines the differences between the secular world (Kingdom of Man or the World) and God’s Kingdom, which includes but is not limited to the Church, and the relationship between the two. While this may all sound like archaic mental gymnastics and a comfortable source of self-justification for churchy people, it is not. The practical implications of this portion of theology are enormous for Christians’ engagement in the world today. Having studied power relationships through critical theory and literature placed a brighter spotlight on it for me.
My criticism of Evangelicalism today stem directly from my understanding of the theology of Two Kingdoms. We (American, evangelical Christians) have largely put our functional faith in the worldly means of political power, capitalism and wealth in order to bring about what we claim to be “spiritual ends” (saving the culture, currying God’s favor for America, etc, etc, etc.) in ways that benefit us and help us maintain power. We have let our effective spiritual tools rust in the shed: faith, prayer, service to anyone, open-handed generosity, love, lovingly sharing the Good News of Jesus, hospitality, valuing all people and the like, dying if it serves the needs of another, etc., because we lack functional faith in the One we claim to trust with our souls. The One we insist others trust with their souls.
The mishandling of this theology either deliberately (see Kuyper) or ignorantly or lazily has had disastrous implications for the witness and work of the Church here. The Christian message is controversial enough, but when we utterly confuse what we are doing and how, we destroy anything we might have to offer.
There are other directions I’m interested in as well (Communion/the Lord’s Table, Eschatology, a clearer (articulable?) understanding of the harmony between my faith and science, and much much more). But this is the clearest example I can give you right now.