“...the rare parts about which there is still uncertainty do not affect in any way any doctrine” Bible Translations, R.L. Sumner
RESPONSE: I totally agree with R.L.Sumner.
In the book “The Story of the Manuscripts” by Rev. George E. Merrill, the 
good Reverend quotes Prof. Arnold as stating:
 
“there are not more than fifteen hundred to two thousand 
places in which there is any uncertainty whatever as to the true 
text..”  
 
Notice how the good Professor manages to first start by alleging that the 
number of “variant readings” are only a fraction of their true number 
(according to him only 1500-2000), 
this number being in the respected Professor’s estimation quite minuscule. He then goes on to explain how all of them are undeserving of his attention with only about a dozen being of any doctrinal importance. In this manner, in one paragraph many thousands of additions, omissions, and “corrections” of the church over the ages are suddenly transformed to only a dozen and then quickly reduced to none. RESPONSE: But the Professor is correct! When the question is over the odd word here or there, or when the question is over whether Matthew records an incident which Luke records anyway, it is clear that doctrine is NOT affected!
Notice 
how casually and quickly centuries of tampering with the text of the “inspired 
word of God” is brushed off and justified?.  For such men the answer is very 
simple.  All of the changes to the text are all “trivial” and “inconsequential.”  
For them only a few thousand, or a few tens of thousands of errors in the 
“inspired word of God” is a very acceptable.  For them it is just a matter of the 
“spirit” of the book.  For them, some of the words of God are not really that 
important and can be disregarded.  Let us see what Jesus (pbuh) has to say 
about such people :
 
“But he (Jesus) answered and said, It is written, Man shall not 
live by bread alone, but by every word that proceedeth out of the 
mouth of God.”
Matthew 4:4
 
We also read in the Old Testament:
“that he (God)  might make thee know that man doth not live 
by bread only, but by every [word] that proceedeth out of the 
mouth of the LORD doth man live.”
Deuteronomy 8:3
 
“Ye shall not add unto the word which I command you, neither 
shall ye diminish [ought] from it, that ye may keep the 
commandments of the LORD your God which I command you.”
Deuteronomy 4:2
 
Look at it this way.  If I were to tell you: “I would like to cut a few small 
pieces from your body.  No more than, say, thirty or forty pieces.”  Would you 
then reply: “Fine.  So long as you do not cut off any ‘important’ or ‘big’ 
pieces.”?  Should we not deal with the scriptures of God the same way?
So it is with the Bible. If the ending is Mark is missing, we still have the resurrection of Jesus described by Matthew, Luke, John, in the book of Acts and in the letters of Paul. Salvation through Jesus is described many times in the Bible, so that the odd error does not affect this.
We live in an imperfect world. All people make mistakes. The church has made mistakes. And the copiers of Scripture have made mistakes. But God has communicated the way of salvation so well, that it cannot be lost even in an imperfect copy or imprecise translation of the Bible. Perhaps your idea of God is that he cannot communicate with us without his message being letter-perfect. But I believe God is greater and more powerful than that. His plans are not hampered by the sins and mistakes of human beings.