MammaBear,
Hi.
Reiki and religion are, as far as I am concerned, two separate issues. ULE is accessible to everyone (including free thinkers) and Reiki certainly may be done in a manner entirely devoid of 'religion' or other organized spiritual dogmatism
:)
And, there are plenty of folks undertaking Reiki who are neither christian or Free Thinker. lol But, if all your students are christian? Well, even among christians there is a lot of variability in what is not thought of as 'heretical' in some way (though the term heresy seems to be left to the catholics most of the time), I have heard really strict Baptists refer to Reiki as a form of heresy.
But, if you need to justify Reiki in religious terms in order to make it more palatable for your students then it is certainly your perogative to couch things in whatever terms you might see as appropriate. How much it bothers you that others may not agree with you is another kettle of dragons, of course.
:)
Cheers,
RC