Reformed theology teaches that we must observe the Sabbath. For some elaborate reason this commandment is singled out and believed that we can do no works on one day a week. There is no guarantee, though, that the things consumed on Sundays were not manufactured on another Sunday. Perhaps the processed food eaten during the week was worked on Sunday; what about the electricity used throughout one's house, that too could have been manufactured on the Sabbath. How about the paper plates you are using on the Sabbath (so the wife won't have to work by doing dishes, just throw them away), were they made on a non-Sabbath day? Who knows? The list of possibilities of the ways we might break Sabbath could be quite long, as you can see from the examples I have given.
From the Westminster Confession, Chapter 21, we read:
VIII. This Sabbath is to be kept holy unto the Lord when men, after a due preparing of their hearts, and ordering of their common affairs beforehand, do not only observe an holy rest all the day from their own works, words, and thoughts about their wordly employments and recreations, but also are taken up the whole time in the public and private exercises of His worship, and in the duties of necessity and mercy.
Matthew 12 tells us that Jesus worked on the Sabbath and upset the Pharisees. On the Sabbath Jesus and his disciples gathered grain to eat.
From Matthew 12, we read:
At that time Jesus went through the grainfields on the Sabbath. His disciples were hungry, and they began to pluck heads of grain and to eat. But when the Pharisees saw it, they said to him, "Look, your disciples are doing what is not lawful to do on the Sabbath." He said to them, "Have you not read what David did when he was hungry, and those who were with him: how he entered the house of God and ate the bread of the Presence, which it was not lawful for him to eat nor for those who were with him, but only for the priests? Or have you not read in the Law how on the Sabbath the priests in the temple profane the Sabbath and are guiltless? I tell you, something greater than the temple is here. And if you had known what this means, 'I desire mercy, and not sacrifice,' you would not have condemned the guiltless. For the Son of Man is lord of the Sabbath." ~ESV
Jesus also healed the man with the withered hand on the Sabbath. Again, Matthew 12 describes what happened:
He went on from there and entered their synagogue. And a man was there with a withered hand. And they asked him, "Is it lawful to heal on the Sabbath?"— so that they might accuse him. He said to them, "Which one of you who has a sheep, if it falls into a pit on the Sabbath, will not take hold of it and lift it out? Of how much more value is a man than a sheep! So it is lawful to do good on the Sabbath." Then he said to the man, "Stretch out your hand." And the man stretched it out, and it was restored, healthy like the other. But the Pharisees went out and conspired against him, how to destroy him. ~ESV
Are we better than our Lord in keeping the Sabbath? No! It is not humanly possible to keep this commandment. No need to fool ourselves. Be honest with Father.
I know that I should listen to His word, hold it sacred and gladly hear and learn it.