“Keep All His Commandments” (Deut 30:8)

Having evaluated how the Bible relates OT law to Christians and having considered some of the errors and dangers in alternative approaches, the discussion below overviews a three-step process for applying OT law today. It then supplies two case studies on commands that Christ’s new-covenant law maintains with extension and without extension.

A Method for Applying OT Law

The following three-step process will help believers faithfully assess through Christ and for Christ the lasting significance of Moses’s law today.

1. Establish the Law’s Original Meaning and Application

a. Categorize the Type of Law:

What type or kind of command are you assessing—criminal, civil, family, cultic/ceremonial, or compassion law? At stake here is the law’s content, not form (e.g., apodictic vs. casuistic).

Criminal Laws	Laws governing offenses that put the welfare of the whole community at risk (i.e., crimes); the offended party is the state or national community, and the punishment therefore, is on behalf of the whole community in the name of the highest state authority, which in Israel meant Yahweh. Examples: Kidnapping, homicide, false prophecy, witchcraft, adultery, and rape.
Civil Laws	Laws governing private disputes between citizens or organizations in which the public authorities are appealed to for judgment or called upon to intervene the offended party is not the state or national community. Examples: Accidental death and assault, theft, destruction of property, limited family issues like premarital unchastity, post-divorce situations, and the mistreatment of slaves.
Family Laws	Non-civil, domestic laws governing the Israelite household. Examples: Marriage, inheritance, the redemption of land and persons, family discipleship, and the care of slaves.
Cultic/Ceremonial Laws	Laws governing the visible forms and rituals of Israel’s household. Examples: The sacred sacrifice, the sacred calendar, and various sacred symbols like the tabernacle, priesthood, and ritual purity that distinguished Israel from the nations and provided parables of more fundamental truths about God and relating to him.
Compassion Laws	“Laws” dealing with charity, justice, and mercy toward others; these laws cannot be brought to court, but God knows the heart. Examples: Protection and justice for the weak, impartiality, generosity, and respect for persons and property.

Table 1. Types of Laws by Content

b. Establish the Law’s Original Meaning and Significance:

Assess the makeup of the law in its original context. Clarify its social function and relative status. Is it central or peripheral to the dominant themes and objectives we find in the rest of the material? Is it a primary expression of Yahweh’s values and priorities, or is it more secondary, reinforcing and supplying an example of a more primary law?

c. Consider the Law’s Original Purpose:

What role did Yahweh intend the law to have in Israelite society? Ask the following: Who? What? When? Where? Why? How? How often? To what extent?

2. Determine the Law’s Theological Importance

a. Clarify What the Law Tells Us about God:

What does the law disclose about Yahweh’s character, desires, values, concerns, or standards? We learn about the unchanging God through his law, and meditating on Moses’s law should move us to worship the Lord and to recognize and grieve over lawlessness as a direct affront to his person. It should also move us to celebrate his provision of Christ as the perfect law keeper and righteousness supplier.

b. Evaluate How Christ Fulfills the Law and Consider Its Impact on Application:

Christ’s person, teaching, and work display the call to love God and neighbor, and Jesus fulfills the law not only in the way he perfectly obeyed it but also in the way that he is the substance of all old-covenant shadows (Col 2:16–17). As we consider how Moses’s law informs the law of Christ, some new-covenant instructions look identical to Moses’s teaching, whereas others are maintained with extension, transformed, or annulled. Because the various types of laws are mixed in the Torah, we must deal with each law on its own.

c. State the Love Principle behind the Law:

If indeed love is what God called the people to do and all the other commandments clarify how to do it (Matt 7:12; 22:37–40; Rom 13:8, 10; Gal 5:14), we should be able to boil down every law into a principle of love. In detail, complete the following statement for every law: The call to love God/neighbor means/implies/impacts/necessitates _______________.

3. Summarize the Law’s Lasting Significance

Here we preserve both the portrait of God and the love principle behind the law but change the context, all in view of Christ’s work. God’s nature is unchanging, but his purposes progress over time. Furthermore, a proper approach to OT law must account for the pattern Christ set for believers and the power he supplies through his victory and his Spirit.

Case Study #1: The Law Maintained with Extension

Our first example of applying Moses’s law is a “slow-pitch, easy-hitter.” It illustrates how some laws get extended into new spheres as times and cultures change.

Table 3. Deuteronomy 22:8

1. Establish the Original Meaning and Application of Deuteronomy 22:8

Flat roofs are common throughout the Middle East, as the roof supplies an extra living space. A parapet is the low wall that surrounds the roof and that protects people from falling off. Hence, a homeowner needs to build his house with a parapet to guard against another’s death. The law’s conditional nature suggests it stands as a secondary application of the more fundamental principle of compassion. Its main purpose was to prevent domestic casualties brought about by mishap or negligence.

2. Determine the Theological Importance of Deuteronomy 22:8

God treasures when humans display his image, and he calls his people to value those made in his image. In Deuteronomy 22:8, Yahweh graciously warns against dangers that could result in injury to others. Similarly, the “golden rule” that Christ advocated (Matt 7:12) is evident in our passage, and it requires that Christ’s followers today love others in the most practical of ways, including how we ready our living space for guests. Hence, the call to love others means we will remove potential dangers and make our living environment safe.

3. Summarize the Lasting Significance of Deuteronomy 22:8

All homeowners bear the responsibility to care for their guests’ well-being. While many societies do not have houses with parapets, Deuteronomy 22:8 is naturally extended to include, say, building a fence around a pool, placing a protective gate above a stairwell, or salting a sidewalk after an ice storm. Love for neighbor is to impact even the littlest details of daily life.

Case Study #2: The Law Maintained without Extension

Much of the world is amid a gender-identity crisis, and the brokenness it is causing is tragic. When read through the lens of Jesus, Deuteronomy 22:5 speaks to this issue.

Table 4. Deuteronomy 22:5

1. Establish the Original Meaning and Application of Deuteronomy 22:5

We should note three features about this prohibition. First, given its use of géber (“man”) rather than ’îš (“man, husband”), the prohibition is not restricted to husbands and wives but includes the broader society. Second, certain articles of clothing, such as a man’s “garment” (ḵ^elî) and a woman’s “cloak” (śimlâ), distinguished men and women in Israelite culture. And third, the fact that cross-dressing is an “abomination” highlights the gravity of the offense and associates it with idolatry (Deut 13:14; 17:4), witchcraft (18:12), and dishonest gain (25:16), which could relate to criminal, civil, or family law.

In this light, Deuteronomy 22:5 appears less a core principle and more a secondary application of more fundamental truths—that there are two biological sexes (male and female) and that one’s biological sex should govern one’s gender identity and expression. As for the purpose of the law, it appears to maintain divinely created gender distinctions.

2. Determine the Theological Importance of Deuteronomy 22:5

Yahweh is passionate about displaying right order in his world. This is the essence of his righteousness, and maintaining gender distinctions is an important part of this order. Moreover, Christ and his apostles continued to distinguish men from women. Indeed, Jesus perfectly exemplified maleness in the way he deeply respected femaleness (see, e.g., Matt 5:27–32; Mark 5:25–43; Luke 7:36–8:3; John 7:53–8:11). In addition, gender distinctions will continue at least until the consummation (Eph 5:22–33; 1 Tim 3:4–5), and even if earthly marriage will end (Matt 22:30), there is no reason to think that gender distinctions will alter in the new heavens and new earth (cf. Rev 21:24).

According to Deuteronomy 22:5, then, loving others and God means that people will maintain a gender identity that aligns with their biological sex and that they will express their gender in a way that never leads to confusion.

3. Summarize the Lasting Significance of Deuteronomy 22:5

Deuteronomy 22:5 helps us recognize the appropriate path for gender expression and the sinfulness of gender confusion, which includes cross-dressing and transgender practice. Western culture still distinguishes men’s and women’s clothing, even if women can at times wear slacks, collars, and ties with no one questioning their femaleness. What was at stake in Moses’s law was gender confusion, and it is from this perspective that our outward apparel matters.

Because Deuteronomy 22:5 focuses on adults and addresses gender confusion, it would not directly dissuade a girl from sporting a mustache in a play or a boy putting on a girl’s dress at home. No viewer of this “child’s play” would be confused regarding the child’s gender. Nevertheless, we must be cautious, because we are always shaping our children, and we live in a society that acts as though gender is a matter of choice rather than providence. This perspective is abominable, and Deuteronomy 22:5 speaks directly against it.

In closing, I call the church to care deeply for the violators and the violated in the present gender-identity crisis. We need to help those struggling with identity to find a new identity in Christ, and we need to help those who have been hurt to find the healing that only Jesus brings. He alone is Savior. He alone is Healer.

¹What follows is abridged from Jason S. DeRouchie, “Confronting the Transgender Storm: New Covenant Reflections on Deuteronomy 22:5,” Journal for Biblical Manhood and Womanhood 21, no. 1 (2016): 58–69.

This blog series summarizes Jason S. DeRouchie’s forthcoming book, Delighting in the Old Testament: Through Christ and for Christ (Wheaton, IL: Crossway, 2024). You can pre-order your copy here.