Are we there yet? How can I know? The book of Hebrews gives us a remarkably practical definition of Christian maturity: “Solid food is for the mature, who by constant use have trained themselves to distinguish good from evil” (Hebrews 5:14, NIV). Notice what the writer does not say. Maturity is not measured primarily by …Are we there yet? How can I know? The book of Hebrews gives us a remarkably practical definition of Christian maturity: “Solid food is for the mature, who by constant use have trained themselves to distinguish good from evil” (Hebrews 5:14, NIV). Notice what the writer does not say. Maturity is not measured primarily by …