What so untruthful as to deserve to be branded sycophantic?

He had so many admirable qualities that it was a shame he could be so untruthful and unreliable.

To tell you the truth, I do not understand in the least how I could have brought myself to be so untruthful.

And she felt surprised that an intelligent young fellow should paint in such an unreasonable manner, so ugly and so untruthful besides.