Meta. Gospel is an Anglo-Saxon word derived from God (good) and spell (story, tidings). It is now universally identified with Jesus Christ's mission and the doctrine that has grown out of it. So when we speak of the gospel it is understood that we refer to religious beliefs that cluster about the teachings of Jesus of Nazareth.
The Holy Spirit is the only authorized interpreter of the gospel of Jesus Christ, and no man or woman can know what His doctrine is except the knowledge be obtained direct from this one and only Custodian. Whoever attempts to set forth His gospel from any other standpoint is acting in the letter, not the spirit. The writings of the New Testament, known as the four Gospels, are the most reliable external guide.