'Gospel of Christ' in the Bible

for though you may have ten thousand christian preceptors, you cannot have many fathers; since it was I that first instructed you in the gospel of Christ Jesus:

'tis for this end I have sent you Timothy, who is my dear disciple, and a faithful christian, who will inform you how I behave my self in every church where I teach the gospel of Christ.

if others partake of your substance, have not I a better title? nevertheless, I have not made use of this privilege; but bear with any thing rather than obstruct the gospel of Christ.

whence then is my reward? why, from my preaching the gospel of Christ gratis, without making use of the privilege which the gospel gives me.