And Moses commanded them, saying, At the end of every seven years, in the solemnity of the year of release, in the feast of tabernacles,

Wesley's Notes

31:10 The year of release - When they were freed from debts and troubles, and cares of worldly matters, and thereby fitter to attend on God and his service.

Jamieson-Fausset-Brown Bible Commentary

10, 11. At the end of every seven years, . thou shalt read this law-At the return of the sabbatic year and during the feast of tabernacles, the law was to be publicly read. This order of Moses was a future and prospective arrangement; for the observance of the sabbatic year did not commence till the conquest and peaceful occupation of Canaan. The ordinance served several important purposes. For, while the people had opportunities of being instructed in the law every Sabbath and daily in their own homes, this public periodical rehearsal at meetings in the courts of the sanctuary, where women and children of twelve years were present (as they usually were at the great festivals), was calculated to produce good and pious impressions of divine truth amid the sacred associations of the time and place. Besides, it formed a public guarantee for the preservation, integrity, and faithful transmission of the Sacred Book to successive ages.

Matthew Henry's Concise Commentary

31:9-13 Though we read the word in private, we must not think it needless to hear it read in public. This solemn reading of the law must be done in the year of release. The year of release was typical of gospel grace, which is called the acceptable year of the Lord; for our pardon and liberty by Christ, engage us to keep his commandments. It must be read to all Israel, men, women, children, and to the strangers. It is the will of God that all people should acquaint themselves with his word. It is a rule to all, therefore should be read to all. Whoever has read of the pains taken by many persons to get scraps of the Scriptures, when a whole copy could not be obtained, or safely possessed, will see how thankful we should be for the thousands of copies amongst us. They will also understand the very different situation in which the Israelites were placed for many ages. But the heart of man is so careless, that all will be found too little, to keep up a knowledge of the truths, precepts, and worship of God.