The next three verses all speak about the seventh Sephiroth - Netzach - Victory or Eternity.
Verse 153. What is the seventh? It is the heaven [called] Aravot . And why is it called heaven (Shamayim)? Because it is round like a head. We learn that it is in the centre, with water at its right and fire at its left. It supports water (Sa Mayim) from fire and water, and brings peace between them. Fire comes and finds the attribute of fire on its side. Water comes and finds the attribute of water on its side. It is therefore written (Job 25:2) , "He makes peace in His high places."
Commentary: Here Netzach is described as heaven. It then speaks of water on the right and fire on the left. Chesed remember is directly above which can be seen as the water of mercy. The on the left is Gevurah and then extended into Hod the eighth Sephiroth. Both Netzach and Hod derive their essence from the central core of Tiphereth spoken of previously. So far just a bunch of symbols. The quote from Job ties it together somewhat and gives it a context. "He makes peace in his high places." What is this peace and what is this high place? First in reverse order the high place is where our thoughts are gathered in holiness following their central imbuement with our heart's desire. This peace is our recognition of stasis in thought and peace of mind due to following the dictates of this heart's desire. Netzach is called Victory because of our ability to overcome obstacles to achieve our heart's desire. Most importantly it is our recognition that we may sometimes stand fast in the holiness of connection resisting all negative attempts to dislodge us from our chosen position. The explanation is continued in the next verse.
Verse 154. Is it then the seventh? Is it nothing more than the sixth. But this teaches us that the Holy Palace is here, and it supports them all. It is thus counted as two. It is therefore the seventh. And what is it? It is Thought that does not have any end or boundary. This place likewise does not have any end or boundary.
Commentary: See how the Bahir makes sure you understand that we are talking directly about the sense of self or being that all of us share. Thought has no boundary meaning that it is Eternal one of the names for Netzach. This Eternity means that within this Holy Palace where our thoughts of our heart's desire are home to we are able to touch and experience the eternity of connection that our heart's desire has been placed there for in the first place. Yes this seventh Sephiroth shares its qualities with its immediate source meaning Tiphereth but there is a further extension as must occur as forms are meant to be awakeness from holiness into embodiment. Now as we move on to the following verse there are indications of what is to come next. Precursors and signs of awareness that having grown is now ready to reproduce itself in kind.
Verse 155. The seventh one is the east of the world. It is from where the Seed of Israel comes. The spinal cord originates in man's brain and extends to the [sexual] organ, where the seed is. It is therefore written (Isaiah 43:5), "From the east I will bring your seed, [and from the west I will gather you]." When Israel is good, then this is the place form which I will bring your seed, and new seed will be granted to you. But when Israel is wicked, [then I will bring] seed that has already been in the world. It is thus written (Ecclesiastes 1:4) , "A generation goes and a generation comes," teaching us that it has already come.
Commentary: Thought that has been immersed within the holiness of our heart's desire produces the Seed of Israel. It is the awakening now of the form beginning as a seed to become full with growth and then its own innate seed making ability. When Israel is good means that when our thoughts keep their focus our heart's desire is made into the seed of its self expression. When our thoughts do not revolve around the focus of our heart's desire and stray to things without they will only bring forth what has already been sown in the world. By definition the creative impulse is diluted. A generation goes and a generation comes speaks to the new life entering and the old life leaving. The generations of thought are what are experienced within the holiness of Netzach. This is why we must learn to always think for ourselves for only then will the truth of our heart's desire be brought home to us. You cannot work another's field and nor can you harvest their bounty without accepting what is by definiton second best for yourself. Sow your own thoughts and look after them to reap their rewards.
For further insights on netzach including some interesting gematria click here