Page 44 in you which was also in Christ Jesus . . . we have the mind of Christ (Php. 2:5; 1 Cor. 2:16). When a son is young, he receives orders from his parents. But as he spends time getting to know his parents and matures, he cultivates an understanding of the mind of his parents in specific situations. The son’s mind, as it were, is renewed to reflect that of his parents. It is the same in the spiritual. We are sons who possess a mind rather than servants who merely take orders (John 15:15; Gal. 4:1ff.). How do we renew our minds? Simply, by spending time in the Lord’s presence, by responding to Him, and by receiving the ministry of His Word, which contains His thoughts. By those three elements our minds are shaped in conformity to His will. The other passage is Hebrews 5:14: But solid food belongs to those who are of full age, that is, those who by reason of use have their senses exercised to discern both good and evil. (NKJV) This text unearths an important principle about spiritual maturity. Namely, that as we practice yielding to the Lord, our spiritual instincts become more acute. The text says that the mature believer has his ,senses exercised by ,reason of use (or habit) to ,discern both good and evil. That is, the mature believer is able to discern the moral will of God in all situations.
The moral absolutes rest upon God’s character. The moral commands He has given to men are an expression of His character. Men as created in His image are to live by choice on the basis of what God is. The standards of morality are determined by what conforms to His character, while those things which do not conform are immoral.
Francis Schaeffer