Ante-Nicene Fathers, Vol IX:
Origen's Commentary on the Gospel of Matthew.: Chapter XIII

13.  The Sacred Half-Shekel.

Moreover to the saying, “They that received the half-shekel came to Peter,” 5914 you will adduce from Numbers that, for the saints according to the law of God, is paid not a half-shekel simply, but a sacred half-shekel.  For it is written, “And thou shalt take five shekels per head, according to the sacred half-shekel.” 5915   But also on behalf of all the sons of Israel is given a sacred half-shekel per head.  Since then it was not possible for the saint of God to possess along with the sacred half-shekels the profane shekels, so to speak, on this account, to them who do not receive the sacred half-shekels, and who asked Peter and said, “Doth not your master pay the half-shekel?” the Saviour commands the stater to be paid, in which was the half-shekel which was found in the mouth of the first fish that came up, in order that it might be given for the Teacher and the disciple.

Footnotes

Matt. xvii. 24.

Num. iii. 47.