According to Osho, Jesus’s line means: 'Whoever is not with truth is against truth.' The 'me' of an enlightened one is egoless; it is truth speaking, not a person. Therefore there is no neutral third position—either you move with truth or you oppose it. This applies to all awakened masters, including Osho.
You can’t sit on the fence: with a true master you’re choosing truth itself, not a person, so you’re either moving toward it or away from it.