Why did the Prophet, peace and blessings be upon him, express distance using a unit of time, namely "a year," instead of using known units of distance, in the Hadith: "And indeed its fragrance can be smelled from a distance of a hundred years"?

A believer must glorify the Messenger, peace and blessings be upon him, and show him proper respect. It is not permissible to assume that what is better was contrary to what he said, for what he said is the best and the most wise.

The Prophet, peace and blessings be upon him, was sent to an illiterate nation, and their most common measure for distances was to define them by time, such as "a day and a night's journey." This suited their understanding due to their frequent travels and their familiarity with the distances camels could cover. Thus, it was part of his wisdom, peace and blessings be upon him, to use the measurements well-known among them to ensure understanding and eloquence.

This conventional estimation is still in use, like "light-year." Pre-Islamic Arabs used terms such as "an hour's journey" and "a night's journey." The Sunnah also mentioned terms like "mile," "finger," "span," "fathom," and others.