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

2.  The Harmony of Husband and Wife.

So much then for the more common understanding of the two or three whom the Word exhorts to be in agreement.  But now let us also touch upon another interpretation which was uttered by some one of our predecessors, exhorting those who were married to sanctity and purity; for by the two, he says, whom the Word desires to agree on earth, we must understand the husband and wife, who by agreement defraud each other of bodily intercourse that they may give themselves unto prayer; 6063 when if they pray for anything whatever p. 496 that they shall ask, they shall receive it, the request being granted to them by the Father in heaven of Jesus Christ on the ground of such agreement.  And this interpretation does not appear to me to cause dissolution of marriage, but to be an incitement to agreement, so that if the one wished to be pure, but the other did not desire it, and on this account he who willed and was able to fulfil the better part, condescended to the one who had not the power or the will, they would not both have the accomplishment from the Father in heaven of Jesus Christ, of anything whatever that they might ask.

Footnotes

1 Cor. vii. 5.