I think, "everything is possible" has been taken by many people and twisted into justification for some really bazaar and pointless practices. From a scientific standpoint, not EVERYTHING is possible. I believe by "everything is possible" the original purpose was to motivate people to do something with themselves like working towards a political career or becoming highly regarded in their field of expertise. I don't think it was originally supposed to be taken as a mantra to be applied to time travel, levitation, or shapeshifting.
Time travel may one day be possible, maybe, but certainly not right now. Not type of magic will send you flying into the future or into the past, magic just doesn't work that way not even astral projection (which is another concept abused by many).