Making and worshipping an idol is foolishness and a lie, because a manmade image can never truthfully represent the Eternal God. For a son of God, worshipping idols is irrational (Acts 17:29); to look to something physical as important or more important than God defies all wisdom. The way the world looks to physical objects is superstition (e.g., good luck charms, religious crosses, shrines).
Martin G. Collins
The Second Commandment
Though God's normal activity involves far more mercy than justice, we have to operate with the understanding, the conviction, that God owes us nothing. He knows exactly what is happening. If He allows a tower to fall on our heads this afternoon, we cannot claim any injustice on God's part. He has already given us so much mercy that it is beyond our understanding.
All of us receive injustices from the hand of men, and we do not deal anywhere near as fairly with each other as we should. We want everything in our dealings with others to go favorably for us, for that is what we feel is fair. Israel is saying a similar thing here.
One thing is certain, however: None of us has ever received the slightest injustice from the hand of God. As we grow in understanding and humility, we begin to see that we have received an overwhelming abundance of grace.
John W. Ritenbaugh
Justice and Grace
Though He had just created the world and everything in it, God had no need for rest. Isaiah writes, "The everlasting God, the Lord, the Creator of the ends of the earth, neither faints nor is weary" (Isaiah 40:28). But Exodus 31:17 shows us how God rested on the first Sabbath: "For in six days the Lord made the heavens and the earth, and on the seventh day, He rested and was refreshed." God's Sabbath rest was a real rest - though He was not tired - because He was refreshed, at ease, and satisfied with His work.
Sharpening Our Saws
It is vital for us to understand that this is where the Sabbath "rest" comes from! God is the source of strength, power, and refreshment. They all come from our relationship with God within the proper keeping of the Sabbath day. He gives it to us as a gift of His grace.
He restores our energy. He gives us the power to overcome and to grow. He gives us peace of mind so that we are truly rested. He helps us to recover our strength. He enables us to live confident, hope-filled lives. He gives us good health and sound minds. "The Lord gives His beloved sleep" (Psalm 172:2). He gives us strength-restoring sleep. All of these things are gifts of grace from time well-spent in fellowship with Him, developing the relationship with Him and communicating with Him in Bible study and prayer.
How we use the Sabbath day tells Him a great deal about how we will do in His Kingdom. I fear that many of us have put the wrong emphasis on it. We tend to look at the Sabbath day as "things that we cannot do" rather than "things we can do" - truly liberating things we cannot devote time to do on the other six days of the week.
John W. Ritenbaugh
Sabbathkeeping (Part 1)