I think he meant that the God-given conscience in people.. it can help prevent them from doing wrong sinful things, yes, from having wrong thoughts or doing evil deeds. But to unspiritual on-lookers who lack discernment and wisdom.. to unbelievers ..it might appear to them in their minds ..that we believer who is taking heed is an uber-weak, wimpy, yes full on coward. They miss, but to the righteous person wanting to please the Lord, it simply means that things in that person are working right as the conscience was designed to work. And when a person becomes a new creation in Christ, the conscience in connection with the Holy Spirit will work all the better for Christ's Cause. Let it, and God will use you to impact lives.
"There is only one way to achieve happiness on this terrestrial ball, and that is to have either a clear conscience or none at all." ~ Ogden Nash
You remember Zacchaeus in the Bible. He was a chief tax-collector at Jericho, and mentioned only in the Gospel of Luke. He was a descendant of Abraham, and became a good example of Jesus' personal, earthly ministry to seek and to save that which was lost.. yes in bring salvation to the unregenerate people.