The Jews believe in God and they believe that God is the creator and they believe that God is only one. Judaism is one of the religion that believes in that so it has received conflict in the past when they are under Roman Rule. The Roamsn believe in many gods but the Jews believe in only one. They have the belief that the same God can have a close relationship. God also is still working in this world that could affect what the people will do.
They also had the faith that they should maintain their relationship with God as they had made a covenant with Him. If they would have that covenant, God would give them good things. That is why the Jews do not just keep the law they had received but also to live a holy life. The Jews believe that they are the chosen people of God still as a covenant between them was made. They also have the sense of community with each other.
One of the customs that is being practiced until today is the circumcision. They do it when the child is eight years old following the rule has given at the time of Abraham. Whatever the Jews do in honor of God can be an act of worship as they strive to live according to the law of God. One could be born as a Jew but does not practice is still a jew. It is hard though for a non-jew to convert and become a jew.