The Church of Christ, Scientist does not release numbers of their membership, which is a unique trait of this church. Maybe the reason is that this is a church that has been steadily losing members. At one time this was a formidable organization, but now it's only a shadow of its former self.
The name Christian Science is actually a misnomer, for this religion is neither Christian, or scientific. It is actually a cult, which is totally at odds with Christianity. Neither does it follows any scientific method, but relies on self-delusions.
These cultists base their beliefs on the writings of Mary Ann Morse Baker. (Also known as Mary Baker Eddy) Her main book is titled Science & Health with key to the Scriptures. Mrs. Eddy affirmed that her book was divinely inspired. However it is doubtful that a divine book would require the numerous updates that her book went through.
Its teachers are called practitioners. They claim to have healed thousands of people, but not one healing has been corroborated by a competent doctor.
They insist that only the spiritual is real that matter is non-existent, that it is just an illusion, and an evil one at that.
Curiously for all their emphasis on the spiritual, their "Quacktitioners" are too eager to get their hands on the monetary fee, which is the sure sign of a materialist. Christian Science is rife with false doctrine. They deny the inspiration of the Bible, The personality of God, The physical death and resurrection of Jesus, and many other things
There is an enormous amount of proof that our modern Bible is a trustworthy representation of the original writings, and it was not infected by some mortal or material sense, as they so boldly proclaim.
God is not some kind of spiritual non-intelligent force. He is a very personal God he has the same feelings of compassion, anger, and love, as we do, for he made us in his own image. If he was not personal it would imply that we humans are better than him.
Jesus did die physically, and resurrected. He did not fake his death, nor was it an illusion. He even offered himself to be inspected by his disciples.
Reaching Christian Scientists is not an easy task, but it can be done. The most important thing is to break through the self-delusion that the world is not real. One can start out by pointing that they eat material food, wear tangible clothing, and feel actual pain. (Maybe a pinch in the arm would help, just kidding)
Although many of them eventually see the errors in their beliefs, and leave of their own accord, we must be there to guide them into the true Christian Science.
We need to beware of our attitude, when we approach them lest by ridiculing their absurd doctrines, we alienate them further from us and drive them deeper into their self-delusions instead of winning them to the lord.