Abraham did not keep the law
Isaac and Jacob, neither
Not so sure Noah, Ham, Gomer or Japhet did.
The Law was only given much later, to prove our iniquities, to accuse, so we could learn that we could not save ourselves.
Jesus fulfilled every letter of the law by becoming our sin, our curse, through bearing it for us. He did not revoke it but fulfilled it. Those not living under His grace alone, choose to be cursed under the law.
Others appreciate what Jesus had done through dying and arising for us. Jesus is our law, our rest, our Sabbath.
Love your Lord God with your whole being and your fellow human like yourself. In doing so, you are keeping every other law. Jesus made it so straightforward.