Frame is comprehensive in laying out the foundation for how we know God and how we live in light of the Scriptures.
2. Systematic Theology by Wayne Grudem [y, l, e, p, s]
A highly readable systematic theology.
3. Reformed Dogmatics vols. 1-4 by Herman Bavinck [p, s]
A solid Dutch Reformed work, translated well in English. It is a pretty technical read but worth the effort.
4. Institutes of Christian Religion (2 vol.) by John Calvin [e, p, s]
Calvin’s classic, need I say more?
5. Systematic Theology by Louis Berkhof [e, p, s]
Fairly readable and thorough systematic.
6. Salvation Belongs to the Lord by John Frame [y, l, e, p, s]
This is Frame’s mini-systematic, a good first systematic.
7. Institutes of Elenctic Theology by Francis Turretin [p, s]
Want to read the text that John Calvin’s seminary used? Charles Hodge/Old Princeton also used this text.
8. The Christian’s Reasonable Service (4 Vol) by Wilhelmus A Brakel [l, e, p, s]
Thanks to Reformation Heritage Books you can now actually find these books in the same place. He was a Dutch Pastor who wrote this 4 volume systematic theology for the people in his church.
9. A New Systematic Theology Of The Christian Faith by Robert Reymond [e, p, s]
Reymond has written a sound Presbyterian systematic theology.
10. Christian Beliefs by Wayne and Elliot Grudem [c, y, l, e, p, s]
This book is a heavily condensed version of #2 on this list. I included Christian Beliefs because the text is understandable to all people of all ages. I think it is important to have at least one book that covers all ages.
Honorable Mention: Christian Theology by Millard Erickson [y, l, e, p, s]
(c=children; y=young adult; l=lay leader; e=elder; p=pastor; s=scholar)