Every Day I'm Drinking the Kool Aid

Of course, the phrase, "drinking the Kool Aid" is a cruel joke.  For those who don't get the reference, the incident on which this saying is based occurred in Jonestown, a colony of a religious nature in which the leader told his people they were going to be persecuted and suggestion the best option for them was to commit suicide.  Women, children, and men were given poisoned Kool-Aid.  They drank it, knowing they would die.
Now, if we accuse someone of drinking the Kool Aid, we mean that they are following an unreasonable belief or committing an illogical action based on that belief.  The suggestion is that they are not thinking for themselves. 
I recently offended a former student by using this phrase.  He had encountered an instructor with a belief system different than his own, and I suggested that before refusing the Kool Aid he perceived the instructor was offering, consider the Kool Aid he had been drinking up to that point in his life.  When he told me he was offended, I apologized.  My apology was not for my suggestion that he had been drinking Kool Aid, but that he was offended by statement.
We are all raised on a belief system.  Some of us will choose to embrace that belief system, some will reject it.  Either action can be performed without adequate thought.  So I suggested to my former student that we are raised on Kool Aid, and we need to constantly evaluate our flavor of choice.  By this I meant that we need to be diligent in giving thought to our beliefs and the groups with which we align ourselves in those beliefs.
I would never suggest to another person to give up their beliefs or attempt to alter their beliefs.  I would consider this doing them harm.  My belief system tells me not to do harm to others.  We have the beliefs we have because they work for us.  Either they aid us to live within society, or they allow us to live with ourselves.  But we must be sure that our beliefs are working for us, and they match up with our conception of morality.
Maybe utilizing this phrase was offensive.  It seemed I was suggesting that he had not thought about his beliefs.  I don't think I would suggest this to him.  However, when presented with a different set of beliefs, his first response was to become offended.  I would suggest the first response should have been to listen, consider, utilize a different way of looking at things to re-evaluate his own beliefs.  Not accept.  Not change his own beliefs.  Just listen, and consider.  My beliefs undergo modifications from time to time, and this is a good thing.  My earth is no longer flat.  And I've learned to brew my own flavor of Kool-Aid, which suits me best.