Deuteronomy 29:29 says, “The secret things belong to the Lord our God, but the things revealed belong to us and to our children forever, that we may follow all the words of this law.” This verse comes at the end of a long passage where the Israelites renew the Mosaic Covenant and its laws before the Lord.
The phrase the secret things belong to the Lord means that there are some things only God knows. He is omniscient, omnipotent, and omnipresent. He is also eternal (Psalm 90:2), knows the future (Jeremiah 29:11), and sees all things (Proverbs 15:3). Unlike God, humans are finite and limited in our knowledge—we cannot fully or completely know everything about God or His purposes. So the “secret things” that belong to the Lord are those things that only He knows as the Creator and Sustainer over all creation (Colossians 1:16–17).
However, the fact that the secret things belong to the Lord does not mean that humans cannot know anything about God. In fact, Deuteronomy 29:29 also speaks of “things revealed.“ We can know a great deal about who God is and what He’s doing because He has revealed Himself to us through “the words of this law,” as Deuteronomy 29:29 says. Though God is mysterious, and certain “secret things” belong only to Him, He has chosen to reveal Himself to humanity through His Word (see 2 Timothy 3:16–17 and 2 Peter 1:20–21). More specifically, God has chosen to make Himself known to us through His Son, Jesus (John 1:14; Hebrews 1:1–3). God wants us to learn and know more about Him as we as we live our lives (Deuteronomy 4:34; Matthew 11:28–30).
So, even though people can never gain knowledge of “the secret things [that] belong to the Lord,” they do have access to what is clearly revealed in His Word about who He is and how He wants them to live.
The words of Deuteronomy 29:29 can also be a source of encouragement for people facing difficult or challenging circumstances. If a parent loses a child, or a woman is abandoned by her husband, or a man loses his job, knowing that “the secret things belong to the Lord” can help them remember that God knows and sees all things. The “why“ of a tragedy may be one of the “secret things“ that God keeps hidden as part of His inscrutable plan. But He has promised to work even the most difficult circumstances for good on behalf of His chosen and loved people (Romans 8:28).