Mormon Dilemma 773 LDS Only True Christians on Earth

Journal of Discourses 14:199; “There is no other people in the world that believe in and practice the Bible as strictly as the Latter-day Saints. None but the Latter-day Saints properly believe in the Lord Jesus Christ; no other people acknowledge him and keep his commandments; and yet they follow us up, their object, professedly, being to convert us to Christianity, but in reality it is to induce us to apostatize until they get the upper hand, that the Priesthood may again be destroyed from the earth.” – Brigham Young, Ogden, Utah, June 3, 1871

Matthew 16:18; “And I say also unto thee, That thou art Peter, and upon this rock I will build my church; and the gates of hell shall not prevail against it.”

 If this teaching was true why didn’t the Lord tell us in the Bible that there’d only be one church on the face of the earth in these “latter days”? 

What did Jesus mean in Matthew 16:18 the gates of hell wouldn’t prevail against His church? 

Where was Mormonism in the days of the original apostles if this is a “restoration” church? 

Where are any writings telling us about Joseph Smith’s religion from the time of Christ?

Where is the proof the apostles were polygamists or that Jesus taught He’d be crucified for polygamy and that God was not a spirit like the Apostle John said in his gospel? John 4:24.

Why is every doctrine in Mormonism the complete opposite of what the Bible says?