"And I, brethren, when I came to you, did not come with excellence of speech or of wisdom.... For I determined not to know anything among you except Jesus Christ and Him crucified" (1 Corinthians 2:1,2).
We are liable to get an idea that we have a system of truth comprising such subjects as the law, the Sabbath, nature of man, advent, etc., and that to this we have superadded a little gospel, the idea of justification by faith. There is but one doctrine we have to preach, that is the gospel of Christ.
Is there nothing besides the gospel to teach? "It is the power of God to salvation" (Rom. 1:16). What do we want besides salvation? What more can we ask for?
The Gospel brings righteousness. The righteousness of God is what God does, His way. To be in harmony with Him is to make His way our way. The gospel reveals this way to us (vs. 17). Not only this, but it is the power of God to work out His way in us. The Bible is a statement of God's way, and is summed up in the ten commandments, which are a declaration of His righteousness (Isa. S1:6, 7).
In Matthew 6:33, Christ declares this righteousness to be the one thing needful. Why? Righteousness is life, and the one who has God's righteousness has everything in this world and in the world to come.
"The just shall live by faith" (Rom 1:17). Nothing else? By faith and works? "Do not add to His words, lest He reprove you, and you be found a liar" (Prov. 30:6). To be just is to be righteous, and a righteous man will do righteous acts. That is the fruit of righteousness. But how does He do these works? By faith. "This is the work of God, that you believe" (John 6:28, 29).
Nothing can be added to the preaching of the righteousness of God by faith of Jesus Christ. What about these doctrines, as the Sabbath, immortality, etc.? Since the "kingdom of God and His righteousness" (Matt 6:33) is the one thing needful, and since there is nothing unimportant in the Bible, all of these doctrines are simply division lines summed up in the doctrine of righteousness by faith. We can preach nothing else, for everything outside of this is sin." [1]
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