Romans 3:6

how shall God judge the world? The emphasis is on "judge," not on "world." It is needless to suppose the word "world" here to stand in opposition to the Jewish people. The point of the question is, that if God could not righteously punish sin when sin illustrated His glory, not only would He not punish those particular sins, but He would (as to principle) entirelyabdicate His office as "Judge of all the earth." Allsin, in one respect or another, illustrates His glory, if only as a black contrast: therefore, in nocase would punishment be just! On the truth that the Lord isthe "Judge of all" the Apostle falls back as on a "first ground."