'Fear' in the Bible

It was because of a revelation that I went up; and I submitted to them the gospel which I preach among the Gentiles, but I did so in private to those who were of reputation, for fear that I might be running, or had run, in vain.

Before certain men came from James, he used to eat [his meals] with the Gentiles; but when the men [from Jerusalem] arrived, he began to withdraw and separate himself [from the Gentile believers], because he was afraid of those from the circumcision.

I fear for you, that perhaps I have labored over you in vain.

Brothers, if a man is taken in any wrongdoing, you who are of the Spirit will put such a one right in a spirit of love; keeping watch on yourself, for fear that you yourself may be tested.