Chief among those sins that are today not thought of as especially sinful- given the near ubiquitous assumption that there exists a hidden clause behind every verbalized commitment that it will be most assuredly done if nothing else more interesting or trivially pressing comes along- is unreliability. Or untrustworthiness. Or unfaithfulness. Or whatever other word sufficiently captures those moments when a man says he will do something but then does not do it.
It seems to me that this character flaw is thought to be of no serious import. Two men agree to do something together. One sees the commitment as having that unspoken asterisk, the other does not and turns down other events or duties that coincide with the prior engagement. And thus, when the first man cancels, having no real good reason for doing so, other than it benefits him, the second man is left holding the bag of disappointment, not only because of his friend’s unreliability, but because he has forfeited scheduling those others things that he would have otherwise done.
This is not right, even if commonplace.
The Sound of Doctrine 