Is Belief in God ethical?

[Dr H]

 If you willfully deny the truth, are you morally responsible for that?

Yes:  we are always to some extent morally responsible for what we do willfully.

Religion, per se, isn't necessarily a willful denial of the truth, however.  One might be ignorant of the truth.  One might believe that various religious precepts are the truth.  

There might be a certain laziness involved there:  e.g., one may not have overly concerned oneself with attempting to test that which is regarded as true.  The moral responsibility in that case is determined by how willfully one avoids searching for or testing that believed to be true.  Some questions dispose themselves to being tested freely; others may rarely come up in a lifetime.  If it never occurred to someone that a particular belief needed to be -- or even could be -- tested, I'd have a hard time putting much moral weight on their circumstantial ignorance.