atrocious stylists

quoted from The magical world of Fernando Pessoa, by Gary Lachman:

But what really troubled the author of The Book of Disquiet is that all these mystic masters were such atrocious stylists. “When they write to communicate… their mysteries,” he said, “[they] all write abominably. It offends my intelligence that a man can master the Devil without being able to master the Portuguese language.” Yet Satanists alone are not at fault. “To have touched the feet of Christ,” Soares tells us, “is no excuse for mistakes in punctuation.”