The power of memory is real. What we can recall from different parts of our life not only shapes our attitude moving forward, it can inspire us to revert back to happier, more stable times.
Or, in the case of Egypt, they could motivate a nation to rest.
Deuteronomy 5:15 isn’t the first time that God uses the memory of slavery in Egypt—a memory that this particular generation wouldn’t have been as familiar with as their predecessors—to drive them to obedience, but it is the first one used in conjunction with the Sabbath.
All the other mentions (Deuteronomy 15:15; 16:12; 24:18; 24:22) are in the context of feast days, or justice, or even Sabbath years. They all encourage Israelites to perform a certain action with a heart of gratitude and mercy, rather than mindless, robotic, obedience.
Think of this instance, for example. When Moses says to “observe the Sabbath day and keep it holy” (Deuteronomy 5:11), and then follows it up by saying they should “remember they were a slave” (Deuteronomy 5:15), you could draw an immediate conclusion that rest was not often given to slaves. Because you weren’t allowed to rest then, do it now.
Or there could be a deeper meaning. Perhaps, because he mentions male and female servants, sojourners, and animals in the verse before, Moses may want them to extend that rest to others, since it wasn’t given to them as slaves (Colossians 4:1)?
Maybe it just has to do with authority. God brought them out “by a mighty hand and an outstretched arm,” so whatever He commands them to do (including Sabbath observance) is what they’re required to do.
I’ll be frank here—I don’t really think it matters that much. Whatever specific connection Moses wanted to make between the Sabbath and Egypt isn’t clear (to me, at least), but it was clear to those people. Egypt was a marker for them, and God used that memory to shape their future.
With that in mind, think back to your own period of metaphorical Egyptian slavery. How can you use that to drive your life as a Christian?
To be clear, I don’t mean a period of intense trial. That wasn’t Egypt to these people—that was the wilderness.
I’m talking about the time before you became a Christian, when you were a slave to the things of this world (Romans 6:15-23). That’s your Egypt. You didn’t know God, might not have cared, and didn’t realize that you were headed towards an eternity of separation from Him.
This is exactly what Paul does in Ephesians 2:11-22. He calls on gentile Christians to remember that period before conversion, when they were “without hope” and “without God in the world.”
That’s who they used to be, but now, because of the blood of Christ, they have been “brought near” to Him (Ephesians 2:13).
Paul does the exact same thing in Ephesians that Moses does here in Deuteronomy 5—he calls on them to remember a period without God to motivate them to stronger obedience with God.
If you’ve been a Christian for any period of time, it’s likely you’ve gone through times where you take your salvation for granted. The best antidote for that, according to Moses (and Paul) is to remember your time in Egypt. If we can remember how hopeless our lives were without God, maybe we’ll take our current situation more seriously.