Jesus Believed in Yahweh

    Yahweh is the name of the God of the Jews in the Old Testament.  It means, literally, something like "I am that which I am."  When Jesus speaks of God in the New Testament, it is clear that he means Yahweh, the God of the Jews.  He is usually speaking to Jews, and when he refers to God, there is no confusion about who he is talking about.  He refers to Yahweh in this example:

When the Pharisees heard that he had silenced the Sadducees, they gathered together, and one of them tested him by asking, "Teacher, which commandment in the law is the greatest?"  He said to them, "You shall love the Lord, your God, with all your heart, with all your soul, and with all your mind.  This is the greatest and the first commandment.  The second is like it:  You shall love your neighbor as yourself.  The whole law and the prophets depend on these two commandments." (Mt 22:34-39, parallels in Mk 12: 28-24, Lk 10:25-28, from Old Testament Dt 6:5, Lv 19:18)

Both of these laws are quotes from the Old Testament.  The first deals with Yahweh.  It is clear both that Jesus believed in Yahweh, and believed that Yahweh deserved total commitment.