Yūsuf 12:7

La-qad kāna fī Yūsufa wa-ikhwatihi āyātun li's-sāʾilīn

"Assuredly, in Joseph and his brothers there are signs for those who ask."

The word was tabulated at al-Ḥujurāt 49/10, and this very verse was cited there as an example:

إِخْوَة (ikhwa) — brotherhood of descent (of lineage). Yūsuf 12/7: in Joseph and his brothers there are lessons — wa-ikhwatihi.

I rely on that treatment. The distinction recorded there was this: ikhwa weighs towards brotherhood of blood, ikhwān towards companionship or brotherhood in religion.

That the word comes in the plural is worth recording: āyāt, not the singular āya.

I give this as an observation about the structure: it is not said that a single lesson is to be drawn from the story. It is reported that there are many signs — and this accords with the length of the sūra and the density of its detail.

لِّلسَّآئِلِين — "for those who ask". Root س-أ-ل.

And the determining of the addressee must be recorded, and I give it as my own reading: the signs are not for everyone but for the one who asks. That is, the yield of the story is tied to the question the reader brings. This accords with the final verse of the sūra: there too the lesson will be reserved for ūlū'l-albāb, those possessed of understanding (111).