az

This little word marks a moment and ties it to what is around it. Most often it points to a particular time and says that something happened, or will happen, right at that point: back then, or by then, or at that future day. It is a favorite way for the storytellers and prophets to fix an event on the timeline.

It also has a second, closely linked use. When it follows a condition (if you do this), it stops being purely about the clock and turns into a connector that means in that case, or then as a result. The time sense and the consequence sense shade into each other, because in everyday speech the next thing in time is often the thing that follows logically.

Readers should not over-read it as a precise marker. It does not pin down an exact hour or even always a clear sequence. It simply says: at that point, then. Context, not the word itself, tells you whether the point is past, future, or hypothetical.

When this word picks up the small attached word for from, it stops naming a single point and starts naming a stretch of time that begins at that point. The sense is from then on, ever since, or from of old. It answers how long, not just when.

Depending on the setting it can reach far back to ancient beginnings, as when wisdom is said to belong to God from of old, or it can mark a near boundary, as when someone dates a change of fortune from the moment a certain thing happened. Either way the point chosen is the starting line, and the meaning runs forward from there.

This is why English Bibles switch words for it here: not then but since, of old, or from the beginning. The same root idea of a fixed point is still underneath, but now the point launches a span rather than locating a single event.