My Mormon friend says that his church is similar to the early Christian church, but when I mention the writings of the early church fathers that clearly demonstrate this is not true, he simply says that the church had fallen into apostasy by the time of these writings. I really feel that I need biblical evidence to dispute his claims. Any help?
Perhaps you will be interested in this thread:
Mormonism: Restoration of Ancient Christian Church?
Yes, there are many LDS apologists that write books and articles attempting to support the claim that the LDS Church is a restoration of the original Church established by Jesus Christ, and that they restore lost and/or corrupted doctrines and practices.
The problem, in my view, is that there simply is no evidence of an ancient Church of Jesus Christ of Former-day Saints. When reading the Bible, as well as the writings of the earliest Christians, you will not find a single, cohesive Church with many of the uniquely LDS beliefs. This is actually the problem that I found with LDS apologetic works on the matter, like Barry Bickmore’s
Restoring the Ancient Church. What it ends up becoming is a hodge podge of sources, from diverse groups (Gnostics, Egyptians, orthodox, etc), sometimes out of context. Further, some of the beliefs and practices that are claimed to be restored were never lost in the first place, such as deification/theosis, temples, apostolic authority, prophets, etc.
But what it comes down to is whether there was a total apostasy of the Church Christ established (and even then, just because there was an apostasy does not automatically lead to one concluding that the LDS Church is the restoration, if one was needed anyway). I have found that none of the verses cited in support of a total apostasy actually support it. Instead, they frequently refer to partial apostasies (which Catholics and other Christians readily accept), are talking about something else (like with the Amos verses), or things are being read into the verse, eisegesis (like with the “not sparing the flock” verse). Instead, we find Biblical support for the continuity of the Kingdom of God, once He established it, that Christ is the head of His body and guides His Church, that the Spirit guides us into all Truth, and that all this can happen despite our failures as humans, as sinners, which a merciful and just God is well aware of.