[Ali Imran]

The Catholics claim that I cannot use that analogy?? but my denomination is Lutheran..nothing to do with the Catholics. 
If you lay in support for their claim..surely you also believe in the Trinity.

Nothing to reconcile with that statement that "Jesus god in the flesh said the Father is the only true god

https://www.gotquestions.org/God-in-the-flesh.html

Sorry for the misunderstanding. I took that article from a Catholic site but it is not just a Catholic thing. That heresy first appeared in the 2nd century.

There are many heresies in Christendom. When it comes to the Trinity, the harder you try to explain it, the more heresy you will be committing, as demonstrated by you when you tried to explain the Trinity using the h2o analogy.