In my opinion, I think there are a couple of signs of those who have achieved a certain level of spirit connection.
The first is that they have integrity. By this, I do not mean anything vaguely related to morals or ethics. I mean that they are whole and their actions reflect this wholeness/holiness. They do not act in ways that are not true to who they are. This leads to a certain consistency in their behavior. You do not see the saint beating his wife, for instance. You see the predator's ambivalence towards others that are not his prey.
This is the result of manifested spirit bringing with it a sense of of place. A quick glance at the tree of life will reveal this. Take a look at Malkuth. See that X in that sephira? That doesn't occur elsewhere. Sure, the division denotes the densest forms of the elements of creation but that is not all is shows. X marks the spot. That point at the center of the X is Hadit.
This hangs pendant too the soul above. The soul has manifested at that point. Hence the sense of place and the lack of erratic, pointless behaviors. This leads to the second marker. The manifested soul acts purposefully. If you see wild swings of behavior resulting the minutia and meaningless interactions of life, chances are you are not observing a manifested soul. The actions observed should align with the person's stated soul purpose. At the very least, behaviors should not interfere with that purpose.