In this context, you must understand that there is a great difference between the partition of the head and the partition of the body. For there are two types of Malkhut in the partzuf:
The first is the fusing Malkhut, which fuses with the supernal light through the force of the partition placed upon it, as stated above. The second is the terminating Malkhut, which arrests the flow of the supernal light into the ten sefirot of the body through the force of the partition placed upon it.54As the author of the Sulam goes on to explain, the vessel of Malkhut, and the partition that rests on it, exists in this system in two forms. The partition that was placed on the Malkhut of the head is used to create the returning light, which enclothes the vessels of the head and allows them to receive the supernal light. This Malkhut can therefore be viewed as facilitating the process of channeling and transmitting the supernal light. It is referred to as the fusing Malkhut because it is able to interact with the supernal light and fuse with it to some extent, generating the returning light through the collision. By contrast, once the Malkhut vessel has expanded downward, forming the body of the partzuf, the partition of the Malkhut of the body does not engage in any fusion with the supernal light. Instead, it serves as a barrier that blocks out the supernal light from fully entering the Malkhut of the body. It is this barrier against which the surrounding light beats. For this reason, the Malkhut of the body is referred to as the terminating Malkhut. This is the meaning of the “force of the partition”: the partition has the power to block the surrounding light from entering the Malkhut of the body.