Genesis 2:1–3 (ESV)
Thus the heavens and the earth were finished, and all the host of them. 2 And on the seventh day God finished his work that he had done, and he rested on the seventh day from all his work that he had done. 3 So God blessed the seventh day and made it holy, because on it God rested from all his work that he had done in creation.

Exodus 20:8–11 (ESV)
Remember the Sabbath day, to keep it holy. 9 Six days you shall labor, and do all your work, 10 but the seventh day is a Sabbath to the Lord your God. On it you shall not do any work, you, or your son, or your daughter, your male servant, or your female servant, or your livestock, or the sojourner who is within your gates. 11 For in six days the Lord made heaven and earth, the sea, and all that is in them, and rested on the seventh day. Therefore the Lord blessed the Sabbath day and made it holy.

Matthew 12:1–8 (ESV)
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. 2 But when the Pharisees saw it, they said to him, “Look, your disciples are doing what is not lawful to do on the Sabbath.” 3 He said to them, “Have you not read what David did when he was hungry, and those who were with him: 4 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? 5 Or have you not read in the Law how on the Sabbath the priests in the temple profane the Sabbath and are guiltless? 6 I tell you, something greater than the temple is here. 7 And if you had known what this means, ‘I desire mercy, and not sacrifice,’ you would not have condemned the guiltless. 8 For the Son of Man is lord of the Sabbath.”