The short version first

tatkṣetraṃ yacca yādṛkca yadvikāri yataśca yatsa ca yo yatprabhāvaśca tatsamāsena me śṛṇu

Hear in brief what the field is, how it changes, where it comes from, and who its knower is.

What it means

Krishna promises a summary before the detail. First the field: what it is made of, how it changes, where it comes from. Then its knower: who that is, and what power it holds. A good teacher gives the outline first, so the student does not get lost.

The story

Arjuna is a trained archer, not a philosopher. His teacher Drona taught him the bow, not the nature of the Self. So Krishna speaks like a mentor on the first day of a hard course. Here is the map. Now let us walk it together.

In your life

On your first day at a new job, a colleague sketches the whole company on a napkin. Five boxes, three arrows. Suddenly the maze makes sense. Before a big task this week, draw your own napkin map first.