Spiritist Magazine – Feb/1858 – Wandering or incarnate spirits
These are the states of the Spirit, which can be incarnated, that is, connected to a physical body, or in a wandering or erratic state, that is, in the interval between one incarnation and another.
To err, in this context, means “to be without the right direction”. It is clear that the Spirit has a course, traced by God, but, as he does not know this course from his imperfection, he only experiences the learning of improvement, he is said to err or that he is in a state of erraticity while he is free from matter, but waiting for a new incarnation.
Pure Spirits, of course, do not fit into this classification, as they no longer need to reincarnate, since they have, theoretically, covered the entire evolutionary scale.