The Torah's 10 commandments are equally relevant. After the beatitudes, Jesus says:
“Think not that I am come to destroy the law, or the prophets: I am not come to destroy, but to fulfil.” (Mat 5:17, KJV)
He says that before giving more commands in the sermon on the mount (the next two chapters of Matthew), much of which extend the old law/10 commandments.
Faith in Jesus is the primary one. There's many given in the next two chapters of Matthew which come after that quote, and I'd say they all hinge upon belief in Jesus and his teachings (i.e., faith).
“Think not that I am come to destroy the law, or the prophets: I am not come to destroy, but to fulfil.” (Mat 5:17, KJV)
He says that before giving more commands in the sermon on the mount (the next two chapters of Matthew), much of which extend the old law/10 commandments.