Of course! Spirits have to manifest in order to damage you. At that moment, they are also vulnerable.

[He shook his head thoughtfully as he looked around that their surroundings.]

If they attempt to attack in force, I'll erect a barrier. It should keep them at bay long enough to get our bearings. I do believe, at the moment, they are doing naught but satisfying a curiosity. Most spirits have little understanding of the physical world, after all.