Viewers have seen Johnson murder his wife's ex-husband and leave his own ex-wife to die following an accident. Most recent scenes aired appeared to show the preacher strangle wife Denise (Diane Parish).
The BBC said in a statement: "Lucas is certainly not intended to be representative of Christians. He is a very damaged and dangerous individual who has created a twisted version of the Christian 'faith' in his mind to hide behind and to convince himself that his actions are acceptable. As the story unfolds, we will see other characters questioning Lucas's claim to be a Christian.
"As Lucas has become increasingly unhinged, his obsession and reliance on the Bible and the scriptures has become increasingly frantic and desperate. This represents this character's emotional breakdown, and it is very clear that this is absolutely not normal behaviour."
It was also confirmed that future scenes will see other characters question Lucas's behaviour.
"In episodes yet to broadcast, we will see the characters Grace, Mercy and Dot - all three of whom are Christians - question and discuss Lucas's frame of mind," the statement concluded.
A BBC Three special, EastEnders: The Murders of Lucas Johnson, will air at the end of the month.