They teach there was an apostasy and the true church ceased to exist on earth.
We need prophets today, the same as in the Old Testament, Mormon Doctrine, p. 606.

The book of Mormon is more correct than the Bible, History of the Church, 4:461.

The debate began with the three following questions:

1)  Jude 1:3 says, "ye should earnestly contend for the faith which was once delivered unto the saints."  Now you say it has been delivered more than once?

2)  Jesus and the apostles came "saying none other things than those which Moses and the prophets did say should come."(Ac 26:22)  So how does your "prophecy" rate above the admonition in  Isa 8:20-- "To the law and to the testimony: if they speak not according to this word, it is because there is no light in them."?

3)  You claim "the true gospel was lost from the earth."  Yet, Pr 22:12 says, "The eyes of the LORD preserve knowledge, and he overthroweth the words of the transgressor."  Who/which of you should I believe and why?  Should I trust "the eyes of the Lord" or should I, instead, trust Joseph Smith?