If we look at someone who is born into a religion, lives their life holding those religious beliefs, and dies as a member of that same religion - is it valid to

If we look at someone who is born into a religion, lives their life holding those religious beliefs, and dies as a member of that same religion - is it valid to assume that they could have separated themselves from their beliefs? Exercise — of both body and brain — is work. Not having done it does not mean one is unable to. Many live entire lives without a taut muscle. Yet we know they could have lived differently.