'Gospel' in the Bible

Now when I came to Troas for the gospel of Christ and when a door was opened for me in the Lord,

And even if our gospel is veiled, it is veiled to those who are perishing,

in whose case the god of this world has blinded the minds of the unbelieving so that they might not see the light of the gospel of the glory of Christ, who is the image of God.

We have sent along with him the brother whose fame in the things of the gospel has spread through all the churches;

Because of the proof given by this ministry, they will glorify God for your obedience to your confession of the gospel of Christ and for the liberality of your contribution to them and to all,

For we are not overextending ourselves, as if we did not reach to you, for we were the first to come even as far as you in the gospel of Christ;

so as to preach the gospel even to the regions beyond you, and not to boast in what has been accomplished in the sphere of another.

For if one comes and preaches another Jesus whom we have not preached, or you receive a different spirit which you have not received, or a different gospel which you have not accepted, you bear this beautifully.

Or did I commit a sin in humbling myself so that you might be exalted, because I preached the gospel of God to you without charge?