Part 1: The underlying spiritual forms seen in prophecy show things... We already know that the spiritual form or picture (תמונה, temunah) that we are talking about is nothing but a light (הארה, he’arah) shining from Malchut, which shines in this particular way because Malchut is the root of the created, “separate” realms in which this form or picture is actually found. It follows that the prophetic vision must be interpreted accordingly: the prophetic image must be understood in accordance with the way the corresponding form appears in the material world.
We refer to the form seen in the prophetic vision as the underlying form (סוד התמונה, sod hatemunah). This is because in the prophetic vision, what is seen is not the physical form as it exists in the material world but rather the spiritual root of this form, and thus we call it the underlying form. The way that the subject of the prophecy must be understood is …in accordance with the nature of each particular form as it actually appears in the lower world. This should now be quite clear.