As I understand it, God created Adam, who had direct communications with God.
According to the questions and answers in these four questions, at the time of Avraham the existence of God had been lost to humanity.
- When did Avraham Avinu become Jewish
- How did Avraham discover that God exists?
- Abraham's converts.....to what?
- Why did God select Abraham, when it also mentions that Abraham didn't even know God's name
I also reviewed 1 & 2 prior to asking they shed some light on the relationship between belief in God and being Jewish. It looks like Avraham was the first Jew and Adam was the last man prior to him who spoke with God.
Was there any recognize of God between Adam and Avraham?