Reddit reviews Comforting Hearts, Teaching Minds: Family Devotions Based on the Heidelberg Catachism

Here are some ideas.

RC Sproul's Essential Truths of the Christian Faith is a great summary of many key ideas.

His The Holiness of God is a classic that packs quite the punch.

Also by Sproul, The Crucial Question booklet series is a great series of shorter booklets that explore a few important topics in a bit more depth without being overwhelming.

Sproul's What is Reformed Theology? is a decent overview that is pretty approachable.

Beeke's Living for God's Glory is a decent introduction that I think can be helpful in that it starts to unpack some of the broader implications.

Looking at creeds and confessions is also solid. Here are decent ones for the Westminster Confession of Faith (and this one too) and Westminster Shorter Catechism and the Heidelberg Catechism.

In case you want to watch instead, Ligonier Ministries will post 1 free video from their teaching series every day.

As for listening, there is Renewing Your Mind

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