A wise old priest once told me to read two old books for every modern book that I read.  There is a lot to be said for the old wisdom.

Like old Hymns, they have stood the test of time.  I like to read a lot of secular works as well as the sacred.  I am answering with an eye toward the sacred. 

Among my favorite old authors are St. Augustine of Hippo, Richard Hooker, Jeremy Taylor, St. Cyprian, Charles Simeon, C.S. Lewis and G.K. Chesterton.  ( I am considering anyone who was alive in 1970 to be modern.)

Among my favorite modern authors are Eugene Peterson, John Eldredge, Peter Kreeft, and D. Martyn Lloyd-Jones.