I have come to the conclusion that Horatius Bonar could never have written a book called A Generous Orthodoxy*.

Be discriminating. Do not call error truth for the sake of charity. Do not praise earnest men merely because they are earnest. To be earnest in truth is one thing; to be earnest in an error is another. The first is blessed, not so much because of the earnestness, but because of the truth; the second is hateful to God, and ought to be shunned by you. Remember how the Lord Jesus from heaven spoke concerning error: “which thing I hate” (Rev. 2:6–15; 1 Tim. 6:4, 5). True spiritual discernment is much lost sight of as a real Christian grace; discernment between the evil and the good, the false and the true. “Beloved, believe not every spirit; but try the spirits whether they are of God; because many false prophets are gone out into the world” (1 John 4:1). This “discernment,” which belongs to every one who is taught of God, is the very opposite of that which is called in our day by the boastful name of “liberality.” Spiritual discernment and “liberal thought” have little in common with each other. “Abhor that which is evil, cleave to that which is good” (Rom. 12:9). The “liberality which puts bitter for sweet. And sweet for bitter” (Isa. 5:20), is a very different thing from the “charity which thinketh no evil” (1 Cor. 13:5).
   Truth is a mighty thing in the eyes of God, whatever it may be in those of men. All error is, more or less, whether directly or indirectly,. A misrepresentation of God’s character, and a subversion of his relation (Rev. 22:18, 19).

—Horatius Bonar, Christ Is All, ed. Michael A. G. Haykin & Darrin R. Brooker (Reformation Heritage Books, 2007), 123–124.