Answer:
God commanded the Jewish People to observe the Sabbath and keep it holy as the fourth of the Ten Commandments. The idea of a day of rest comes from the Bible story of the Creation: God rested from creating the universe on the seventh day of that first week, so Jews rest from work on the Sabbath.
Lenin was a Marxist, as were his successors. He had a vision of making the Soviet Union a country where everyone will be equal, earning the same amount of money, everything will be available to everyone, the country to be self-sustainable. While this may seem as a nice idea, in practice in turned the total opposite. The Soviet Union became one huge concentration camp where around 30 million people lost their lives because they had another political opinion, belong to certain ethnic group, and were people that had it better and succeeded in life. The people were poor, often suffering from malnutrition because of the misjudged planning of the high officials. The economy was not in good condition and was developing very slowly. The country was ruled by a dictator that used violence in order to sort all the problems.
This is a bit complicated:
Cuba was under Fulgencio Batista's reign by the time of Castro's rise. Cuba was a capitalist country at that point that was basically the US' puppet. Fidel Castro and his "guerrillas" were obviously against the system that was being employed for many reasons. I believe one of the main reasons was that Batista's Cuba was a corrupt one. There were many under-the-books assassinations just because they were a threat to Batista, etc. Overall, Cuba was a very corrupt and injust country at that point and that is why Fidel decided to fight against it, beginning with the "27 de julio movement" alongside Ernesto "Ché" Guevara.