8. But whoever desires to have a conscience thus void of offence, let him see that he lay the right foundation. Let him remember, _other foundation_ of this _can no man lay, than that which is laid, even Jesus Christ_. And let him also be mindful, that no man buildeth on him but by a living faith; that no man is a partaker of Christ, until he can clearly testify, _The life which I now live, I live by faith in the Son of God_; in him who is now _revealed_ in my heart; who _loved me, and gave himself for me_. Faith alone is that evidence, that conviction, that demonstration of things invisible, whereby the eyes of our understanding being opened, and divine light poured in upon them, we _see the wondrous things of_ God’s _law_, the excellency and purity of it; the height and depth and length and breadth thereof, and of every commandment contained therein. It is by faith, that beholding _the light of the glory of God, in the face of Jesus Christ_, we perceive, as in a glass, all that is in ourselves, yea, the inmost motions of our souls. And by this alone can that blessed love of God be _shed abroad in our hearts_, which enables us so to love one another as Christ loved us. By this, is that gracious promise fulfilled, unto all the _Israel_ of God, _I will put my laws into their minds, and write_ (or engrave) _them in their hearts_, Heb. viii. 10. Hereby producing in their souls, an entire agreement with his holy and perfect law, and _bringing into captivity every thought to the obedience of Christ_. And as an evil tree cannot bring forth good fruit, so a good tree cannot bring forth evil fruit. As the heart therefore of a believer, so likewise his life is thoroughly conformed to the rule of God’s commandments. In a consciousness whereof, he can give glory to God, and say, with the apostle, _This is our rejoicing, the testimony of our conscience, that in simplicity and godly sincerity, not with fleshly wisdom, but by the grace of God, we have had our conversation in the world_. 9. _We have had our conversation._ The apostle in the original, expresses this by one single word (ἀνεστράφημεν). But the meaning thereof is exceeding broad, taking in our whole deportment, yea, every inward as well as outward circumstance, whether relating to our soul or body. It includes every motion of our heart, of our tongue, of our hands and bodily members. It extends to all our actions and words; to the employment of all our powers and faculties; to the manner of using every talent we have received, with respect either to God or man.