Fortunately, Christ left us with a Church, guided by the Holy Spirit.
Gee, I wish this article had footnotes to show the sources.
I'd really like to see one of Eusebius' books that had a page 152. Or any page numbers for that matter.
http://www.tertullian.org/fathers/index.htm#Demonstratio_Evangelica_(The_Proof_of_the_Gospel)
Closer yet, He's gifted us with the indwelling o fthe Holy Spirit in every believer through faithin Christ.