To whom our fathers would not obey. — The historical parallelism is continued. The people rejected Moses then (the same word is used as in Acts 7:27) as they were rejecting Christ now, even after He had shown Himself to be their redeemer from a worse than Egyptian bondage.
In their hearts turned back again into Egypt. — The sin was one often repeated, but the history referred to is probably that in Exodus 16:3. For a later example see Numbers 11:5.