This conflict is core to the Jewish belief system. In the book of Bereishis (Genesis), Abraham, the forefather of the Jewish people, is called by G-d and told to "go for yourself, from your land, and from your birthplace, and from your father's house, to the land that I will show you." Why would G-d do this?
What I see in Eid Al-adha is something else: a celebration with deep connections to both Christianity and Judaism. The deepest of those connections is the spectacle, past and present, of countless deeply devout people taking a sacred story into their own hands as if it were a clump of soft clay and remaking it in their own image.
Abraham experienced multiple traumas that included suffering and pain and sorrow. As we are all his children, then that means that we must accept that our lives will also include pain and suffering and sorrow. To be Jewish means to suffer and to stay Jewish is to be resilient. We are not let in on God's master plan.
Is religion fading in Britain? According to the latest influential British Social Attitudes Survey (BSA), just released this December, half of us Brits do not belong to any religious grouping or affiliation.