When [the Holy Spirit] comes, he will convict the world concerning sin and righteousness and judgment: concerning sin, because they do not believe in me; concerning righteousness, because I go to the Father, and you will see me no longer; concerning judgment, because the ruler of this world is judged.
John 16:8-11

#yeshua came to call the Jews to repentance. He sent the Spirit to call the whole world. And how does the Spirit admonish the world concerning their sin if not through the lives and words of righteous, God-fearing people?

The natural extension of believing in Yeshua is obedience. If you don't obey the words of Yeshua--not some nebulous Law of Jesus that nobody can define--then you don't believe. The Holy Spirit has no commandments of his own, but only teaches the commandments of God and convicts the world of disobedience to the commandments of Yeshua, which are the same as the commandments of God.