Someone asked: in Luang Phor's teaching about merit "flowing for seven days," is that number fixed, or does it relate to the difference in the flow of time between nibbana and the human world?

Merit Flows Seven Days Before and After a Great Ceremony

Pra Ajarn explains that before a great merit ceremony begins, a current of merit is sent ahead from nibbana so that the preparations can succeed — every stage of preparation depends on merit to support it; without that support, nothing could come together. Anyone who, in the seven days leading up to the event, purifies their heart and sets their faith in advance, can connect with this current. Preparation, of course, begins even earlier than that, but the current becomes distinctly clear and strong starting seven days before the event. After the ceremony concludes successfully, the current of merit remains bright for another seven days, continuing to benefit the world. Anyone who keeps that merit in mind during this time continues to receive its brightness — both the seven days before and the seven days after depend on a bright, radiant sphere of faith arising in the heart to receive it.

The Day of the Ceremony Is the Brightest Point

Those organizing the event and those performing the sacred rites receive the full current across all seven days on either side, while participants receive it fully on the day itself. The brightness peaks on the day of the ceremony, then gradually recedes — yet throughout the full seven days before and seven days after, it remains strong.

Why Seven Days

This length of time isn't fixed; it depends on the strength of the merit-sphere according to the conditions of that particular era — in a different age, the window could be longer or shorter. It's similar to how, after doing something good, we feel a lingering sense of fulfillment for a while before it gradually fades — the duration depends on how great the merit generated was each time.