We can find the answer at Revelation 14: 6: “I saw another angel flying in midheaven, and he had everlasting good news to declare as glad tidings to those who dwell on the earth, and to every nation and tribe and tongue and people. ”
منظور از انجیل جاودانی همان « بشارتِ ملکوت » یا مژدهٔ آمدن حکومت خداست .‏