What is the strangest law in the Bible? For many, it is Deuteronomy 22:11, “You shall not wear a garment of different sorts, such as wool and linen mixed together.” This directive is repeated in Leviticus 19:19. The phrase “garment of different sorts” is from the Hebrew sha'atnez, literally “mixed stuff,” which Orthodox Jews define as specifically wool and linen together, not any other mixture.

The Law of Sha'atnez, they feel, is a chok, a decree that the King has passed for His subjects, for which we do not know the reason. Rabbinic commentators believe that many of God's statutes are of that sort. He provides no reason and expects us to accept them on faith. One rabbi has said, “Why ask why?” Their point has validity, certainly, but is there really no reason for this edict? Can we discern God's original point here, and does this mandate have any significance for Christians today?

A spiritual principle is involved here: the principle of separation. Just as God wanted the physical nation of Israel to be kept separate from the nations around it, we are to maintain spiritual separation from the sin that surrounds us.

Deuteronomy 14:2 says essentially the same thing to the children of Israel: “For you are a holy people to the LORD your God, and the LORD has chosen you to be a people for Himself, a special treasure above all the peoples who are on the face of the earth” (see Exodus 19:5). For this reason, Israelites were not to mix wool and linen, nor mix physically with those around them.

With this understanding, we can bring the principle to the New Testament and apply it under the New Covenant:

Do not be unequally yoked together with unbelievers. For what fellowship has righteousness with lawlessness? And what communion has light with darkness? And what accord has Christ with Belial? Or what part has a believer with an unbeliever? And what agreement has the temple of God with idols? For you are the temple of the living God. As God has said:

“I will dwell in them and walk among them. I will be their God, and they shall be My people.” (II Corinthians 6:14-16)

The part that Paul quotes at the end—“I will be their God, and they shall be My people”—is found in at least a half-dozen Old Testament verses (Jeremiah 24:7; 31:33; 32:38; Ezekiel 11:20; 37:23, 27; Zechariah 8:8). More importantly, the apostle clearly indicates that the principle still applies! Except now it is God's church that is separated out.

Further, Paul writes in Titus 2:14, speaking of Christ, “Who gave Himself for us, that He might redeem us from every lawless deed, and purify for Himself His own special people, zealous for good works.” One interpretation of this law asserts that wool stands for works and linen represents grace, and the two can never be mixed. But does not the apostle Paul do just that in this verse? Christ gave Himself for us, to redeem us from sin, which is grace. Then he goes on to say that Jesus did this to purify us, to set us apart, to make us a people “zealous for good works.” He redeemed us by grace so we could strive to live a sinless life, which we fail at repeatedly. But we try. The laws of God give us our borders, our limits. Without them, there would be no sin (Romans 3:20).

I Peter 2:9, describing the church, the apostle Peter writes, “But you are a chosen generation, a royal priesthood, a holy nation, His own special people, that you may proclaim the praises of Him who called you out of darkness into His marvelous light.”

Where does this leave us in terms of Deuteronomy 22:11 and Leviticus 19:19? Just as not circumcising one's baby boy would not be a sin, since it is not a sign under the New Covenant, so with mixing wool and linen. However, there are proven health benefits to circumcision. God is not capricious that way; there is great good in following His instructions, even if they are no longer binding under the New Covenant. It would not be surprising if there are health benefits to not mixing these fabrics as well. Certainly, all of one or the other produces a better quality garment.

For us today, however, the takeaway is to keep ourselves spiritually pure, to concentrate on not mixing with the sin of this world, for we are “a chosen generation, a royal priesthood, a holy nation, His own special people.”