—Leviticus 20:4-5 (NASB)
Of all the false religions, that of Molech was the worst. It required one to offer their own child as a burnt offering. Among many other justifiable reasons for this to be singled out as bad by God, one of the most prominent is how this practice was an almost opposite mirror of what God would do through giving His only Son, an unholy twisting of God's ultimate plan. Worship of Molech was not just going after a false religion, it was following something that twisted the very foundations of God's ways into the most offensive version possible.
There is a difference between people who struggle with issues rooted in sinful behavior and those who pursue alternative paths to God. One deserves our mercy and compassion; the other our total and complete rejection. The difference between a sinner and a heretic is that the sinner struggles with obedience to God's ways, whereas the heretic leads himself and others astray by encouraging disobedience to God's ways. One is trying to stick to the Way, the other is trying to establish an alternate route.
We are called to help and guide the spiritually weak. But for the spiritually deceived and deceiving we are called to draw the line and separate. One needs our love, the other God's Truth. Just as someone in crisis has little use for someone to arrive in the middle of it and give a cold, calculated description of why everything is wrong (too much truth with too little love), so someone instituting the wrong spiritual practices can't be loved out of their choices (too much love with little or no truth).
There are a lot of New Age and other practices creeping into churches with the general thought that they "supplement" faith, such as yoga, chanting, labyrinth walking, etc. If you're wondering who's supposed to draw the line and make the distinction clear to them, the answer is "us". Otherwise, to knowingly allow such to continue makes us a guilty party with them because even if we manage to remain free from their influence, we won't be able to say the same for all the others who don't.†††