I don’t consider it witchcraft—to me, it’s exercising the inherent spark of creation every one of us is born with.
If you're religious, remember that Jesus himself tried for the longest time to get his harebrained disciples to use manifestation. Throughout the New Testament, he pushes them to perform miracles and despairs when they’re too dumb to do it.
There’s the story of the father who brought his son who was suffering from demonic infestation to the disciples, but they couldn't drive out the demon. So he had to go to Jesus… and Jesus was pissed.
He said (and I quote): “You faithless and perverse generation, how much longer must I be with you? How much longer must I put up with you?”
In other words: “You’re too stupid to walk and chew gum at the same time. You should know how to do this by now. I’ve just about had it with you. Didn’t I teach you anything?”
And the disciples were all like, “Sor-ry… but hey dude, why the heck didn’t this work when we tried?”
Jesus answered (and I quote): “Because of your little faith. For truly I tell you, if you have faith the size of a mustard seed, you will say to this mountain, ‘Move from here to there,’ and it will move; and nothing will be impossible for you.”
Unfortunately, his words were interpreted by the church fathers (and now most Christians) to be a metaphor. I don’t think they are.