Time and Eternity; "God, the Universe, and Everything"

This may be an over simplification, but there is the idea around in protestant circles that Constantine created the Catholic "religion," eclipsing "true" Christianity in the 4th century. So there were no Christians, (except, perhaps a tiny remnant,) until Luther rediscovered true Christianity at the dawn of the 16th century.
I was actually taught this, by omission, in my Presbyterian Sunday School. Church history went from the first Christmas to the Diocletian persecutions, (early 4th century,) and then nothing happened until John Wycliffe translated the Bible, (late 15th century.) Our Protestant brethren, it seems, blithely condemn generations of their ancestors to Hell. As sad and misguided as this is, worse its blasphemous, thus idea actually calls God a liar!
Before we go on remember who is the "Father of lies," (John 8:44.) The very first recorded lie; "you shall not surely die," (Genesis 3:4,) was uttered by Satan in the garden, how, how can our protestant brothers call God a liar? The fact is, though, they do! I'll explain...
Scripture is pretty clear on this. It tells us that it is not God's will that any should perish, (2Peter 3:9,) and Jesus tells us that the gates of He'll will not prevail against the Church, (Matthew 16:18.) So, if we have something over 1,000 years in which effectively no one was saved, let's see now, a generation is roughly 40 years so that’s twenty-five generations, now the world-wide population estimate for AD 400 is 256, 000,000 times 25 equals 6.4 billion people went to Hell, with virtually no opportunity to be saved!!
God allowed Satan to co-opt the Church, in contradiction to Jesus' own words, and allowed 6.4 billion souls to perish, in contradiction to the stated will of God! If this scenario is true then God is, indeed a liar, as Satan asserted in Genesis, and if God is a liar, then everyone's salvation is in jeopardy, and the Scriptures cannot be trusted!
Thanks be to God we know He isn't a liar, as the Apostle Paul assures us, "let God be true, and every man a liar," (Romans 3:4.) Add to that that we know, as stated above just who the father of lies is, we have Jesus' word for it, the Devil. These Protestants, ignorant of Church history, even their own, fail to realize that the original reformers, Luther, Calvin, and Zwingli were all Catholic priests. They had all come to salvation In the Catholic Church, they'd studied the scriptures in the Catholic Church, Luther was, in fact, a professor of theology and sacred scripture, his first lecture, in 1513, was on the Book of Psalms.
Luther was a Catholic Christian determined to reform his church, not to shatter it. And shatter it he did! That Old liar, the Devil and Satan, using politics, both secular and religious, to turn the reform into rebellion and a generation of warfare, destroying the Church of Jesus Christ. But God turned cursing into blessing....Within one hundred years, the counter-reformation had addressed all of Luther's ninety-five thesis, and though the conflict has endured to our day, the Gospel is preached. When someone, not of the disciples was casting out demons in Jesus' name, Our Lord said "no one doing miracles in my name can say anything against me," (Mark 9:38,39,) and as Paul said, when people were preaching Christ in order to cause more trouble for him while in prison, "in every way, whether by false motives or true, Christ is preached," (Philippians 1:15-18.)
God works through believers, (unbelievers for that matter,) whether Protestant or Catholic to bring to Christ whomever He calls. So, as Paul so eloquently said; "Let God be true, and every man a liar!.." The issue is that the Gospel is preached!! Amen.