It is simple

I was looking for a simple evidence of a doctrine I already believed, that Prophets of God could not lead astray. I found many arguments, mostly founded on a quote from Wilford Woodruff saying

“The Lord will never permit me or any other man who stands as President of this Church to lead you astray.”   

And whenever a single person is used to defend a point it is not successful in it's attempt to persuade. I even read many points of others seeing the alluring attractiveness of what they asserted, but I already knew what I believed, I was only looking to know where this belief started, I doubted that it started with Wilford Woodruff. Then, the matter was greatly clarified for me in this scripture: 

24 For there shall arise false Christs, and false prophets, and shall shew great signs and wonders; insomuch that, if it were possible, they shall deceive the very elect.

It is found in the gospel of Matthew chapter 24. It is simple. If it was possible to lead the saints astray the prophets would have done so, even the very elect, whatever that constitutes. But, It is not possible regardless what we are inclined to think is reasonable, if we follow the prophet we will be right in the eyes of the Lord, this also provides a second witness to Wilford's claim, though it doesn't need one.