The fourth command tells Israel* to remember the Sabbath day. They were to keep it as a holy day.
The word Sabbath means rest. The first time we hear about a day of rest is in the very first chapters of the Bible.* God made all things in just six days. When he finished the work, he did two things. He looked at all he had made and said, ‘This is very good.’ Then he rested. He took the seventh day and rested from the work of making all things. God did not rest because he was tired. He rested to enjoy what he had made.
The next time we hear about Sabbath is just before God gave the ten commands to Moses.* God had brought the people out of Egypt.* They were in a desert place. There was not enough food there. There was not enough water there. The people were hungry. Their animals needed food and water too. So, God gave them food and water. He gave the people birds for meat. He gave them a special food called ‘manna.’ It was like bread. When they got up in the morning, they found the bread on the ground. All they had to do was gather it and eat it. But they could only gather enough for one day. If they gathered too much, the bread would spoil on the next day, and they could not eat it.
But there was one day that was different. On the sixth day, they were to gather enough manna for two days. Because, God said, ‘The next day will be a sabbath.’.  They were not to do any work on that day. No manna would be on the ground on that day either. That day, they were to rest. They were to remember that God had brought them out of Egypt. They were to remember that God had set them apart from all other people on the earth.
The next time we hear about Sabbath, is here, in the fourth command. The command became part of the covenant* that God made through Moses. From that day on, the people were to do their work on the first six days of each week. But on the seventh day, the Sabbath day, no one was to work. The fathers and mothers could not work. Their sons and daughters could not work. Their servants could not work. Even their animals had to rest. This day was holy. 
But one day of rest in seven was not the end of God’s Sabbath commands. God told them that the seventh year was also holy for them. In that year, they could not plant or gather a harvest. They were to rest. They were to allow the land to rest too. And like the first sabbath, God would provide enough food for them. God would bless* their crops. What they would grow in the sixth year would be enough for the next year too. And in that year, the people were to forgive* the debts of anyone who owed them anything.
The Sabbath was a sign to Israel. It reminded them of the covenant God had made with them. God gave them the Sabbath to remind them that they were his chosen people. They were the people that God delivered from Egypt. He had brought them out of Egypt so they were no longer slaves. He set them apart for himself.They were not like any other nation. No other nation had a Sabbath rest as they did.
Now Israel had to remember this day in all that they did. They bought and sold. They planted and gathered the harvest. They made things and traded things. But they always had to remember that the Sabbath was coming.
We do not keep the Sabbath today as the people of Israel did. But the fourth command reminds us of many important things. God has made us. God has set us apart for himself. We are God’s chosen people. And just as God rescued Israel, Jesus* has rescued us. We are no longer slaves to our sin.* For we have believed the promise of Jesus. ‘Come to me, all of you who are tired. Come, all of you who are carrying a heavy load. I will give you rest.’  Now we are to set every day apart for God. Whether we buy or sell, plant or gather, work or rest, we are to do them all for God’s glory.* Not only that, but we also are to have hope.* Another time of Sabbath is in our future. One day, Jesus will return. He will rule as Lord* and King in a New Heaven* and a New Earth. All who know Him will rest. There will be no more pain or death. There will be no more guilt* or fear or shame. Our souls* and bodies will have found complete joy and rest in Jesus.