There were a few different taxes in Ancient Israel, but one of the most fascinating was that of the Temple Tax:

Then the Lord said to Moses, “When you take a census of the Israelites to count them, each one must pay the Lord a ransom for his life at the time he is counted. Then no plague will come on them when you number them. Each one who crosses over to those already counted is to give a half shekel, according to the sanctuary shekel, which weighs twenty gerahs. This half shekel is an offering to the Lord. All who cross over, those twenty years old or more,are to give an offering to the Lord. The rich are not to give more than a half shekel and the poor are not to give less when you make the offering to the Lord to atone for your lives. Receive the atonement money from the Israelites and use it for the service of the tent of meeting. It will be a memorial for the Israelites before the Lord, making atonement for your lives.” (Exodus 30:11-16)

At first, this might strike us as an unfair regressive tax.  A half-shekel might be a pittance to a wealthy man, while to the poor tenant farmer, this is a great financial sacrifice. All throughout the Old Testament, though, there seems to be an acknowledgment of the different responsibilities that greater or lesser wealth places on those who possess it. Yet here we are faced with a straight, flat tax. Is this a callous requirement neglecting the poor by placing a disproportionate burden on them? Did Yahweh forget the poor here?

In his commentary on Exodus, John Durham suggest something else is going on here:

The sum thus fixed was not by any standard a large amount, but the instruction that rich and poor alike were to give precisely this payment is an important indication of the equality with which all men were received in Yahweh’s Presence. They were all to give equally because they were all to be received and remembered equally; the money was to be used for the expense of the Tent where Yahweh by appointment came to meet them. (Comment on 30:16-17)

Similarly, Craig L. Blomberg says,

The flat rate ensured that even the poorest, who might not be required to give nearly so much via the various tithes, would have to give sacrificially at least here. —Neither Poverty, Nor Riches: A Biblical Theology of Possessions, pg. 47

The equality of tithe speaks to the equality of persons before God. All stand equally condemned before a holy God in need of atonement, and all are equally welcomed into his reconciling presence in the Temple. None can claim greater rights to God’s peace and covenantal blessing, through payment, or inherent extra worth. None ought feel unworthy to come to him in prayer simply because of a lower financial stature. The tenant-farmer’s life is to be redeemed at the same cost as the mighty land-owner’s.

In other words, everybody’s worth a shekel in God’s eyes, which, I suppose, is an Old Testament way of saying “The ground is level at the foot of the Cross.”

Soli Deo Gloria