“The carpenter or his apprentice sees on his tool handle the wearing away caused by his fingers and thumb, but he does not necessarily know that so much has been worn away today, so much yesterday and so much at another time. In the same way, one living devoted to the practice of meditation does not know that so much of the defilements have been worn away today, so much yesterday and so much at another time. He merely has the knowledge that they are being worn away.”
Samyutta Nikaya |||.154