In Shakespeare's "King Henry VI, Part 3," the quote emphasizes the importance of integrity and reliability. The speaker suggests that once someone has betrayed trust, they should not be relied upon again. This idea reflects on the fragility of trust and how difficult it is to rebuild once it's been broken. A betrayal can lead to lasting consequences, making it vital to choose wisely whom to trust.
Additionally, the quote serves as a warning about the nature of loyalty and the impact of deception in relationships, particularly in a political or personal context. The underlying message encourages vigilance in assessing others' character and the potential ramifications of misplaced trust.