The secret things belong to YHVH our God, but the things that are revealed belong to us and to our children forever, that we may do all the words of this law.
Deuteronomy 29:29

The revealed and hidden can be interpreted several ways. Here are some, but you may be able to think of more:

-Deal with those sins that are committed in public. Let God deal with those that are committed in secret.
-Obey God's commands, even if you don't understand them.
-Don't mess with spirits, astrology, and other forbidden sources of corrupted knowledge.
-Those who have forgotten their identity as Israel are still known to God. He knows who you are, and he will find you.