Posted On January 31, 2020

God Has Spoken, So We Must Obey Him

In the biblical perspective, we have not heard God rightly unless we do what he says. Deuteronomy 5:1 says, “And Moses called all Israel, and said unto them, Hear, O Israel, the statutes and judgments which I speak in your ears this day, that ye may learn them, and keep, and do them.” Deuteronomy 6:3 says, “Hear therefore, O Israel, and be careful to do them” (ESV). Allan Harman writes, “Not only were the people of Israel to listen to the stipulations of the covenant, but they were to order their lives in obedience to them.”1

Deuteronomy describes the theological task as a work of remembrance, which refers not to bare mental impressions upon the memory, but to perpetually and faithfully embracing God’s Word to direct one’s life according to his covenant,2 as opposed to forgetting the Lord and his covenant.3 Spiritual remembrance produces obedient action: “And thou shalt remember . . . and thou shalt observe and do these statutes” (Deut. 16:12). Conversely, forgetting God and his covenant results in disobedience: “Beware that thou forget not the Lord thy God, in not keeping his commandments, and his judgments, and his statutes, which I command thee this day” (8:11). Ignatius wrote about AD 100, “Study, therefore, to be established in the doctrines of the Lord and the apostles, that so all things, whatsoever ye do, may prosper both in the flesh and spirit; in faith and love; in the Son, and in the Father, and in the Spirit.”4

Hearing and remembering God’s Word requires more than just reciting texts from the Bible, for God’s law does not explicitly regulate every situation. Rather, it requires a worldview that takes into account the whole counsel of God in order to guide the whole life. Therefore, the obligation to obey God’s Word necessitates the theological task, for obedience requires the engaging of one’s whole mind to discern God’s will by the integration of his various revelations into a unified whole. Without systematic theology, we cannot apply the fullness of God’s Word to our lives.

God Has Spoken, So We Must Teach Others of Him

The fact that God has spoken necessitates our teaching his Word to other people. Deuteronomy envisions two kinds of teaching: domestic teaching in the home and ecclesiastical teaching in the assemblies of God’s people. Teaching the family and teaching the church are closely related, for the Lord commanded Moses to teach the people so that they would teach their children (Deut. 4:9–10, 14; 5:31). The theological task has multigenerational ambitions, aiming to inculcate the fear of the Lord into “thou, and thy son, and thy son’s son” (6:2; cf. Ps. 78:1–7). Israel must hear the words of the Lord and keep them upon their hearts in order to “teach them diligently unto thy children,” permeating every activity of life with an ongoing conversation between “thou” and “thy son” about God and his Word (Deut. 6:7, cf.11:19). Good theology bears fruit in accurate and skillful catechisms and other tools by which people in every age group may drink in the doctrine of the Lord as their spiritual milk.

Moses possessed a unique office as the preeminent prophet of the old covenant. God entrusted a continuing teaching office to the priests (Deut. 17:9–12; cf. Mal. 2:1–9). The Lord said to the people through Moses, “Do according to all that the priests the Levites shall teach you: as I commanded them, so ye shall observe to do” (Deut. 24:8). Thus, it was written of the sons of Levi, “They shall teach Jacob thy judgments, and Israel thy law” (33:10). The old covenant priesthood with its rituals passed away at the sacrifice of our Great High Priest, Jesus Christ, but in the ministers of the Word in the new covenant church, the teaching office continues (1 Tim. 3:2; 2 Tim. 2:24; Titus 1:9). The perpetuity of this teaching office requires the training of men in sound doctrine and the refutation of error, and thus the work of theologians.

John Calvin said of God’s pastors, “They must all their life long endeavor to maintain the doctrine, and therewithal they must have their mouths open to preach the word that is committed unto them, to the end that that treasure be not lost nor buried, but that all men may be made partakers thereof.”5 Thus, theology serves missions.

God Has Spoken, So We Must Glorify Him

The most famous call to hear the Lord appears in Deuteronomy 6:4–5: “Hear, O Israel: The Lord our God is one Lord: and thou shalt love the Lord thy God with all thine heart, and with all thy soul, and with all thy might.” God has spoken, and we must love him. All our study, obedience, and teaching aims at returning to the Lord the all-encompassing love that he deserves from us. Such love expresses itself in exclusive worship, the fear and service of the Lord alone (vv. 12–14). Calvin queried in his catechism (Q. 6), “What is the true and right knowledge of God?” and answered, “When we know Him in order that we may honour Him.”6 We must do theology because God has spoken, and we must glorify him according to his will.

Orthodox theology aims at doxology. Deuteronomy 10:12 indicates that worship is the sum of all God teaches us in the Word: “And now, Israel, what doth the Lord thy God require of thee, but to fear the Lord thy God, to walk in all his ways, and to love him, and to serve the Lord thy God with all thy heart and with all thy soul.” By contrast, the greatest disaster into which a people can fall is to serve other gods.7

The highest purpose of God’s redemptive acts is to distinguish himself from all false gods and idols, so that he alone is glorified as God (Deut. 4:15–19, 32–40). Sound theology teaches us the nature of the true God, so that we will not worship “them which by nature are no gods” (Gal. 4:8). We do not want to fall under Christ’s rebuke to the Samaritans, “Ye worship ye know not what” (John 4:22). Johannes Wollebius said, “Christian theology is the doctrine concerning God, as he is known and worshiped for his glory and for our salvation.”8

True theology not only directs whom we worship but also regulates how we worship. After forbidding Israel to imitate the other nations in the manner of their worship, the Lord said, “What thing soever I command you, observe to do it: thou shalt not add thereto, nor diminish from it” (Deut. 12:32). The doctrine of God’s holiness and a biblical ecclesiology teach us to be zealous in worshiping God according to his command, and not the inventions of man’s will (Col. 2:20–23).

We must do theology because God has spoken, and we must glorify him according to his will. Without sound doctrine, “man’s nature, so to speak, is a perpetual factory of idols,” as Calvin said, for “man’s mind, full as it is of pride and boldness, dares to imagine a god according to its own capacity.”9 Kelly Kapic writes, “Whether it is the distant and uninterested deity of modernity or the fragmented and territorial gods of postmodernity, all times and cultures carry the danger of warping our worship.”10 However, Calvin said, “If we will know whether we have profited in God’s law or no, we must always sift and search ourselves whether we have such desire and zeal that God should be honored and glorified by us.”11 Thus, the theologian should not be motivated by merely accumulating knowledge, but, as Richard of St. Victor (d. 1173) said, by “the fervor of my burning soul.”12

This is a guest article by Joel Beeke, author of Reformed Systematic Theology (Reformed Experiential Systematic Theology series) Volume 1: Revelation and God. This post originally appeared on; used with permission.


  1. Allan M. Harman, Deuteronomy: The Commands of a Covenant God/em>(Fearn, Ross-shire, Scotland: Christian Focus, 2007), 75.
  2. Deut. 5:15; 7:18; 8:2, 18; 9:7; 15:15; 16:3, 12; 24:9, 18, 22; 25:17; 32:7.
  3. Deut. 4:9, 23, 31; 6:12; 8:11, 14, 19; 9:7; 25:19; 26:13; 31:21; 32:18.
  4. Ignatius, Epistle to the Magnesians, chap. 13, in ANF, 1:64.
  5. John Calvin, Sermons on Deuteronomy (1583; facsimile repr., Edinburgh: Banner of Truth, 1987), 1206.
  6. Reformed Confessions of the 16th and 17th Centuries in English Translation: 1523–1693.
  7. James T. Dennison Jr. 4 vols. Grand Rapids, MI: Reformation Heritage Books, 2008–2014., 1:469.
  8. Johannes Wollebius, Compendium Theologiae Christianae, prolegomena (1), in Reformed Dogmatics, ed. and trans. John W. Beardslee III, A Library of Protestant Thought (New York: Oxford University Press, 1965),insins (29).
  9. Calvin, Institutes of the Christian Religion. Edited by John T. McNeill. Translated by Ford Lewis Battles. Library of Christian Classics 20–21. Philadelphia: Westminster, 1960, 1.11.8.
  10. Kapic, A Little Book for New Theologians: Why and How to Study Theology. Downers Grove, IL: IVP Academic, 2012, 18.
  11. Calvin, Sermons on Deuteronomy (1583; facsimile repr., Edinburgh: Banner of Truth, 1987), 266.
  12. Richard of St. Victor, On the Trinity: English Translation and Commentary, trans. and ed. Ruben Angelici (Eugene, OR: Cascade, 2011), 3.1 (116).

Related Posts

Deborah Howard- HELP! Someone I Love Has Alzheimer’s

Deborah Howard- HELP! Someone I Love Has Alzheimer’s

On today’s Equipping You in Grace show, Dave and Deborah Howard discuss Christian friendship and support in and out of the local church, advice for family members and friends with family or friends who have memory loss, the local church, and supporting family members...

When Sinful Comparison Rears Its Ugly Head, Draw Near to Jesus

When Sinful Comparison Rears Its Ugly Head, Draw Near to Jesus

I’d done it again. It was subtle, and neither my husband nor any of our five children sitting in the car with me knew what I had done. That’s how sneaky sinful comparison can be. While reading during a long road trip, right in the middle of a well-crafted sentence in...

The Jews and the Resurrection

The Jews and the Resurrection

Romans 11:13-15, “13 Now I am speaking to you Gentiles. Inasmuch then as I am an apostle to the Gentiles, I magnify my ministry 14 in order somehow to make my fellow Jews jealous, and thus save some of them. 15 For if their rejection means the reconciliation of the...

Riches for the World

Riches for the World

Romans 11:11-12, “11 So I ask, did they stumble in order that they might fall? By no means! Rather, through their trespass salvation has come to the Gentiles, so as to make Israel jealous. 12 Now if their trespass means riches for the world, and if their failure means...

Why God Forgets Our Sins

Why God Forgets Our Sins

On today’s episode, a listener writes in and asks Dave, “Does God forget our sins?” What you’ll hear in this episode The Lord Forgives and Forgets Our Sin. The Christian and Assurance. Forgiveness and Assurance. The Apostles Creed and Forgiveness. Micah and...


Submit a Comment

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.