A more thorough explanation:

Firdfare is an old English word that means a summons to military service or an exemption from military service. It comes from the Saxon words "fird" which means "military service" and "fare" which means "a going".

Example 1: When the king needed soldiers for his army, he sent out a firdfare to all the able-bodied men in the kingdom.

Example 2: Some people were granted firdfare because they were too old or too sick to fight in the war.

These examples illustrate how firdfare was used in the past to either call people to military service or exempt them from it. The first example shows how a firdfare was used to gather soldiers for the army, while the second example shows how some people were exempted from military service due to their age or health.