Ralph Martin took the ‘Full Gospel’ to various Romanist churches and campuses, and it simply branched out from there. What had been a "come out" movement, was now being characterized by a "come in" attitude. Neo-Pentecostalism’s lack of emphasis on any kind of doctrinal distinctions at all — other than an insistence salvation is at least two steps (baptism in water and baptism in the Holy Spirit) — has made it one of the slipperiest heresies in Church History.
Pentecostalism is the exact opposite of the Reformed Faith. There can never be a marriage of the two, because they are diametrically opposed to one another. While the Reformers and their modern followers maintain that Scripture and it alone is sufficient for all faith and practice, we are assured by Pentecostalists that "new" revelations are necessary — to be truly spiritual. The Reformed faith informs us that Christian maturity is the result of God conforming us to the image of the Second Person of the Godhead; but Pentecostalism claims instant spirituality that is evidenced by nonsense-syllables, oracles and "miraculous" healings.