สติเกิดขึ้นได้สองทาง คือการที่เรากำหนดเอง โดยตั้งใจวางใจไว้ที่จุดใดจุดหนึ่ง เช่น เท้าหรือลมหายใจ และการที่สติเข้ามาเองเมื่อกุศลเข้ามาชี้นำให้ระลึกได้ พระอาจารย์อธิบายว่าถ้าไม่ได้กำหนด ใจก็ไม่มีฐานที่ตั้ง สติจึงเกิดขึ้นไม่ได้ แต่กำหนดตรงไหน ใจจะถูกวางไว้ตรงนั้น ดวงสติก็ตั้งขึ้น ดึงพลังบุญเข้ามาขจัดมลทินในใจให้เบาบางลงเรื่อยๆMindfulness can come about in two ways: by deliberately setting it, directing attention to a point such as the feet or the breath, or by arising on its own when a wholesome quality steps in and reminds us. Phra Ajarn explains that without setting attention anywhere, the mind has no base and mindfulness cannot arise. But wherever attention is set, the mind is placed there, an orb of mindfulness is established, and it draws in the energy of merit that gradually clears away defilement.
A student once asked: I still do not quite understand about setting — can we really set it ourselves, or does mindfulness sometimes just arise on its own as we go along in a situation? How is having mindfulness different from being without it?
Setting Mindfulness Means Placing the Mind at a Point
Phra Ajarn explained that having mindfulness means recollecting, being aware. If we are to set it, we must decide where to place the mind. For example, setting it at the feet — the feet touch the ground, cold, hot, soft, firm — we know this because mindfulness has been established. Then shift to setting it at the breath instead: breathing in, we know; breathing out, we know — we know this because mindfulness has been established as well. Wherever we set our attention, the mind is placed there. Once the mind goes in to know the orb of knowing, the orb of mindfulness is established right there.
Phra Ajarn gave further examples: try setting your attention on an egg in the refrigerator, and you can perceive the egg in the refrigerator. Set it on an orange or an apple in the refrigerator, and you can perceive that too. Set it on a cold bottle of water in the refrigerator, and you can set your attention there as well.
Without Mindfulness, the Mind Has No Base
Without mindfulness, the mind drifts aimlessly, unable to find where to settle. This is the difference between having mindfulness and being without it: being without mindfulness means not knowing where the mind is, because nothing has been set, so the mind has no base to stand on. Mindfulness can only arise where the mind is — it cannot arise anywhere else. If the mind does not know where it is, there is nowhere for mindfulness to appear.
Mindfulness That Arises on Its Own Means a Wholesome Quality Has Stepped In
As for mindfulness that arises on its own, without our deliberately setting it, this means a wholesome quality has entered and points us toward recollecting. So in every moment, we should keep asking ourselves whether we have mindfulness right now or are lacking it. If we have mindfulness, we should know where it is set, because wherever we set it, the mind is placed there. Once the mind goes in to know the orb of knowing, the orb of mindfulness is established right there.
When the Orb of Mindfulness Arises, Defilement Grows Lighter
Once the orb of mindfulness is established, it draws the energy of into the center of its brightness, driving the system of wholesome qualities to clear away the stains of defilement, making them lighter and lighter until they are gone. Once nothing remains holding the mind back in the coarse dimension, it is freed from the coarse dimension into a subtler dimension, growing finer and finer on its own, automatically.