It suggests a sense of privilege or favor being bestowed upon someone.
Here are some examples:
* "The king vouchsafed an audience to the humble peasant." (The king granted the peasant an audience, making it seem like a special favor.)
* "The gods vouchsafed their blessings upon the land." (The gods granted their blessings, implying it was a gift and not something they were obligated to do.)
The word "vouchsafe" can also mean to declare or affirm something. For example:
* "The witness vouchsafed his knowledge of the crime." (The witness declared what he knew about the crime.)
However, this usage is less common than the first meaning.
Overall, "vouchsafe" is a formal and somewhat archaic word, so it's not used very often in everyday conversation.