a non practicing jew is still a jew ?

[Tintinass]

Is it true that if a non-practicing Jew is still a Jew?

the opposite for other religions

that it's not just "a religion" but "a way of thinking, a state of mind"?

A rather extreme example.

a Moroccan but not just any Moroccan,a Muslim Moroccan but from a Jewish family forcibly converted to Islam by the Almohads is what he can still be considered Jewish?

[Götterfunke]

Jewish is an ethnicity. Judaism is a religion. Ethnically (genetically) a non-practicing Jew is still a Jew. Religiously, not so much.

[Aldaris]

There's that ethnic/religious duality to this. Now, your religious affiliation doesn't have an effect on the ethnic aspect of it, so sure, non-practicing Jew is obviously a Jew in that sense. In a religious sense? Of course not, by definition. Not sure where this confusion comes from, this answer would be obvious in case of any other ethnic group, but I admit the usage of that word in English is pretty dumb. A better way would be to use the term Jew so it would refer only to 'of Jewish biological origin' and for a practicing Judaist, well, how about to actually call that guy Judaist?