Why in the world would God tell His people to do such seemingly random things? Of course, there are some practical considerations involved – it’s hard to see how a huge ox and a tiny donkey could possibly pull a yoke with the same strength or at the same speed (verse 10). Likewise, planting a vineyard with several different kinds of vines would make harvesting difficult, and might well result in some undesirable cross-breeding (verse 9). But you can find elegant wool-linen blend clothing (verse 11) with a simple online search. So what gives?

Well, the key to the passage may be found in verse 12, which tells God’s people to wear tassels on the corners of their garments. For if we look back at the end of Numbers chapter 15, where this commandment is first given, we find the reason for it: the tassels were to be a reminder of “all the commandments of the Lord,” a reminder to obey God, “and not follow after your own heart and your own eyes, after which you played the harlot,” a reminder to “be holy to your God” (Numbers 15:38-40).

So, since the word “holy” means both to be set apart for God and to be set apart from sin, it’s likely that separating seeds and animals and fibers were other ways of reminding the people to separate themselves from sin, and to remember that God had separated them from all the other people in the world, making them His own special people, high above all the other nations which He made, holy to the Lord (Deuteronomy 26:18-19).

Okay, so is verse 5, which prohibits women from wearing men’s clothes (and vice versa) just the same sort of ceremonial reminder? Probably not. For notice that it comes between the injunction to help struggling animals and the commandment to make sure that wildlife is not harvested at an unsustainable level. The commandment to preserve sexual distinctions is thus placed between other laws obviously intended to protect and preserve life, and to make sure that the natural cycle of reproduction continues. And whatever else the contemporary blurring of the lines between masculinity and femininity may mean, it certainly has the result of fewer people bearing children – for neither transgender individuals nor same-sex couples are fertile.

So, no matter how sincere and honest and heartfelt our attractions may be, no matter how much our own heart and our own eyes might lead us toward any kind of sin (Numbers 15:39), we are to remember the reason for those tassels: We are called to be a holy people, set apart from sin and set apart for God. And that means we must measure the righteousness of our thoughts, words, and deeds according to the Word of God alone – no matter how little sense some of it may make to us.

Deuteronomy 22:4-12 (NASB)

4 “You shall not see your countryman’s donkey or his ox fallen down on the way, and pay no attention to them; you shall certainly help him to raise them up.
5 “A woman shall not wear man’s clothing, nor shall a man put on a woman’s clothing; for whoever does these things is an abomination to the LORD your God.
6 “If you happen to come upon a bird’s nest along the way, in any tree or on the ground, with young ones or eggs, and the mother sitting on the young or on the eggs, you shall not take the mother with the young;
7 you shall certainly let the mother go, but the young you may take for yourself, in order that it may be well with you, and that you may prolong your days.
8 “When you build a new house, you shall make a parapet for your roof, that you may not bring bloodguilt on your house if anyone falls from it.
9 “You shall not sow your vineyard with two kinds of seed, lest all the produce of the seed which you have sown, and the increase of the vineyard become defiled.
10 “You shall not plow with an ox and a donkey together.
11 “You shall not wear a material mixed of wool and linen together.
12 “You shall make yourself tassels on the four corners of your garment with which you cover yourself.