Thus their original essence (as simple Havayahs) already indicates their root (through the fourfold form=AV=72). Then afterwards their particular functions still also point to their root, to show that even in their individual aspects they remain attached and bound to Arich Anpin, which is the root.
...because this is in accordance with their essential being... i.e. as an order of simple Havayahs. But when their letters are filled – which is when they become different from one another... It is quite clear that in their aspect of being Havayahs they are identical, and it is in their filled or expanded forms that they differ. The intention may be explained as follows: in their intrinsic essence they are all equal – they are all lights of one kind, for they are all the name of Havayah, blessed be He, and as such they all indicate their root in the same way. However, their individual functions are different, and this is seen in their filled or expanded forms. It is therefore necessary that each function should indicate the overall root in accordance with its specific nature in order to show that in this aspect too it is attached to its root, and this is its particular meaning. Thus: