Our text, which you should read from your Bible, speaks of the danger of departing from God's Word by allowing its Truth to 'slip' (to drift as a boat from shore). This suggests a loss due to failing to give attention to something which gradually drifts away from us. Verse 3 continues the thought by using the word 'neglect', meaning 'to be careless of'. When we become careless concerning God's Word by letting Truth 'slip', we are in danger of chastisement.
From Deuteronomy 4, we have an admonition from Moses given to the new generation of Israelites who were about to enter the Promised Land. Because there were dangers there, Moses gives instruction to them warning to 'take heed...and to keep their souls diligently, lest they forget the things they had seen and depart from them, from their hearts. Rather, they are to teach them (the things they had seen) to their children and grandchildren.
The context indicates that he is speaking concerning the giving of God's Law to their nation, which was to be their national constitution. I contains instructions on how to live together socially, how to be governed and how to worship God.
He then proceeds to warn them of the sad consequences of departing from Truth and turning their hearts away from God...but, he also gives them hope should they depart, by showing them the way back. Deut 4:29
" But if from thence thou shalt seek the LORD thy God, thou shalt find him, if thou seek him with all thy heart and with all thy soul." KJV He then instructs them to consider these consequences, knowing Who God is. Deut 4:39
" Know therefore this day, and consider it in thine heart, that the LORD he is God in heaven above, and upon the earth beneath: there is none else. KJV
Try as we may to deny the existence of God, and try as we may, as a society to remove Him and His Truth from our lives, the facts remain and circumstances give evidence, that a life, or a nation that seeks to live without God's Truth comes to ruin. We are free choose whether to believe and obey or not; but we are not free to choose the consequences of our choices.
I suggest that the many social problems we struggle with, both as individuals and nationally is due to the fact that we have let slip those Truths we once sought to obey. We let slip the 10 Commandments, removing them from our homes, hearts and public to the extent that we have ignored "Thou shalt not kill (murder)" and have failed to teach them to successive generations, so that now, human life has little value. There are consequences to neglecting God's Truth and exchanging it for the lies of fallen, depraved and sinful man.
There is hope, if we will avail ourselves to it. If we will repent and return and obey from the heart...for at the heart of the matter, is a matter of the heart.
Cleland B. McAfee wrote the beloved hymn "Near to the Heart of God", sing it today!