The neighbor then the house

Yes. The line you are remembering from Rumi, Book VI is drawing on a very old Islamic maxim associated with the Prophet Muhammad:

“The neighbor, then the house.”

Arabic: الجار ثم الدار (al-jār thumma al-dār)

The fuller formulation is often given as:

“First the neighbor, then the house; first the companion, then the journey.”

al-jār thumma al-dār; al-rafīq thumma al-safar.

There is actually an important nuance about attribution: the short maxim is widely attributed to Muhammad, but some hadith scholars have regarded the precise wording as coming from an early Muslim rather than as a securely authenticated prophetic saying.

What Muhammad was getting at

The idea is much deeper than simply “check out your neighbors before buying a house.”

It means that the human environment you enter is more important than the physical setting you purchase.

A beautiful house with hostile, intrusive, dishonest, or miserable neighbors can become a miserable home. Conversely, an ordinary house among generous, decent, mutually supportive people can become a wonderful place to live.

Islamic tradition makes this especially strong because Muhammad repeatedly emphasized the rights of neighbors. There is even a tradition in which he is said to have sought God’s protection from a bad neighbor in one’s permanent home, precisely because a temporary traveling neighbor eventually goes away.

And there is a beautiful related formulation:

“A righteous neighbor is among the causes of happiness; a bad neighbor is among the causes of misery.”

Why Rumi uses it

Rumi takes this ordinary piece of practical wisdom and turns it inward.

When Rumi says, essentially, “the neighbor, then the house,” he is inviting you to think beyond real estate. The house can become a metaphor for the spiritual dwelling—the place in which the soul lives. And the neighbor can become the spiritual company surrounding you.

So the principle becomes:

Before choosing the place in which you will live, choose the company in which you will live.

That is profoundly Sufi. Your companions, teacher, friends and spiritual environment gradually shape the condition of your own soul.

And this makes the second half—“the companion, then the journey”—particularly powerful:

Don’t merely ask, “Where am I going?” Ask, “Who will I become by traveling with these people?”

That is probably why Rumi brings Muhammad’s little saying into the Masnavi: an apparently mundane instruction about selecting a house becomes a spiritual law—your environment enters you.

And there is a wonderfully practical modern application: when choosing where to live, the quality of the neighborhood may actually matter more than the quality of the house. An economist even used the phrase “Choose the Neighbor before the House” as the title of a study of how neighboring firms affect one another.

If you give me the exact translation of Book VI, lines 3015–3025 that you’re reading, I can unpack exactly what Rumi is doing with Muhammad’s saying in that particular passage—the surrounding verses make the metaphor considerably richer.