While studying the fifth command of God’s decalogue (Exodus 20, Deuteronomy 5), it occurred to me that there is a different projection of the fifth command as compared with the fourth:
The Sabbath command first looks back.
The honouring of parents then looks forward.

Remember the Sabbath, keep it holy
Since God rested on the seventh day of creation
Since YHWH delivered us out from Egypt, out of the house of slavery

Honour (glorify) your father and mother
So that you may live a long life in the land that YHWH your God is giving you

The fifth command assumes the natural course of outliving one’s parents. It also suggests that looking forward doesn’t exclude remembering the past. So we provide for parents as they become dependent in old age, since we were dependent on them while we were young, and we live as their representatives after they have departed.

The fifth command helps us also with the fourth command of remembering, since parents are a former generation, which also helps us with the previous three that we would honour and glorify our heavenly Father in the fullness that we have witnessed through past generations.

Yet the fifth command then looks ahead to a long life (indeed eternal life). Wisdom in obeying the fifth command is then helped by looking ahead to the following commands.

We honour parents in honouring our brother as an equal, which extends beyond our household to our neighbour and all who are made in God’s image. “Do not murder” (do not harm, do not hate) is the first practical recognition of this equality, assigning a personal responsibility outside our most immediate household.

We honour parents by growing to maturity and separating from them. We ought to separate from being dependent on them, which prepares the way for them to be dependent on us. “Therefore a man shall leave his father and mother and hold fast to his wife.” Marriage is the perfect expression of this separation in maturity. “Do not commit adultery” (do not flirt, do not lust) is a recognition of the sanctity of marriage. The bond of marriage is a bond like no other. Parents need this separation from children so that they would be prepared to be honoured in eternal rest through letting go of the current life that is perishing, a hope that is analogically realized through being able to rest on their children’s maturity for coming generations. So marriage is the sanctified institution to provide offspring for generations to come, which is a glory to the parents of old.

Separation from parents is also recognized by us having title to our own property. “Do not steal” implies that we are entitled by just means to have property of our own that is not owned by parents or the government. For even the civil government will perish, but God remains the ruler of all things and bestows gifts on his children.

We honour our parents in building a reputation of our own. To glorify our parents is not merely to bear their reputation but to even improve upon it by being a faithful witness to God in Christ. “Do not bear false witness against your neighbour” regards a personal reputation that is built on truth.

And it is important that we don’t even covet (desire in our thoughts) the reputation, the goods, and the spouse that God has gifted our neighbour, even the things which God has gifted our children as they grow to maturity.

If a parent, or even a civil governor says, “you are still a child, you depend on me,” it is an imperative for us to grow up in all of God’s commands so that we can set appropriate boundaries. For, in the end, we all must serve the one everlasting God, who grants eternal life to all his children.