1 How shall the young direct their way?
What light shall be their perfect guide?
Your word, O Lord, will safely lead
if in its wisdom they confide.
2 Sincerely I have sought you, Lord;
O let me not from you depart;
to know your will and keep from sin,
your word I cherish in my heart.
3 O blessed Lord, teach me your law,
your righteous judgments I declare;
your testimonies make me glad,
for they are wealth beyond compare.
4 Upon your precepts and your ways
my heart will meditate with awe;
your Word shall be my chief delight,
and I will not forget your law.
This text from the 1912 Psalter is a paraphrase of the "Beth" (second letter of the Hebrew alphabet) stanza of Psalm 119. In these verses of the psalm (9-16), directed specifically at the young, the psalmist professes delight in God's word (or law) as a guide for living. But that word also calls for obedience from all God's creatures, young and old alike.
Bert Polman, Psalter Hymnal Handbook
It is vitally important that worshipers understand the role of God’s law among us. God gives his law to us, not so that we can earn his favor by full obedience, for even those converted to God cannot obey this law perfectly. Heidelberg Catechism, Lord’s Day 44, Question and Answer 114 says, “In this life even the holiest have only a small beginning of this obedience.” Instead, says Heidelberg Catechism, Lord’s Day 2, Question and Answer 3, through this law “we come to know [our] misery.”
Yet in their new life of gratitude, God’s children “with all seriousness of purpose, do begin to live according to all, not only some, of God’s commandments” (Heidelberg Catechism, Lord’s Day 44, Question and Answer 114). They measure their good works of gratitude as “those which are done out of true faith, conform to God’s law, and are done for God’s glory” (Heidelberg Catechism, Lord’s Day 33, Question and Answer 91).
In other words, though Christ has fulfilled the law for us, “The truth and substance of these things remain for us in Jesus Christ…[and] we continue to use the witnesses drawn from the law and prophets to confirm us in the gospel and to regulate our lives with full integrity for the glory of God according to the will of God” (Belgic Confession, Article 25). Therefore, the Ten Commandments with explanation are included in the third section, “gratitude,” (Lord’s Days 34-44) of Heidelberg Catechism.