D'var Torah: Yoseph had two prophetic dreams which foretold that he would become a king. After his initial joy at the prospect of becoming king, Yoseph experienced great difficulties. Specifically, at the hands of his brothers, who sold him into slavery. Yoseph assumed that the sore troubles that befell him revealed that he was unworthy for the fulfillment of the prophecy. Since he concluded that he had lost the merit to be king, he asked the royal cupbearer to intervene with Pharoah on his behalf. As a result of trusting in a human agency, HaShem lengthened his stay in jail by two additional years. However, since humility is the essential virtue, why was he penalized for deeming himself unworthy? The answer is that even if Yoseph's spiritual status had declined, he was still obligated to trust in HaShem. His faith in HaShem's infinite compassion would have brought about the fulfillment of his prophecies. Regardless of his spiritual status, HaShem would have rescued him and made him a king.
Moral: HaShem's unbounded compassion is far greater than any sin. Therefore, if a person considers himself unworthy of HaShem's redemption, he is accountable because he lacks faith in HaShem's infinite compassion.
Application: Never despair of HaShem's love for you. Even if you sense that you are unworthy, place your heartfelt trust in HaShem, and he will save you from all of your troubles
(Based on the commentary of Rabbi Yisrael Salanter)