[Aquila]

It is my understanding that in ancient Israel the tithe was essentially an agrarian land tax that helped to sustain the Levites, the Temple, and to fill the storehouse with grain and produce to serve the needy classes of Israel (widows, orphans, strangers, etc.).

In essence, it was a land tax that provided for the priesthood and the agrarian welfare system over which they presided.

Prior to this, a "tithe" was a tribute given to a ruler to gain favor and to form alliance. For example, Abraham's tithe of war spoils to the King of Salem.

The tithe could also be a part of a vow. For example we see this with Jacob's tithe.