This was said by the Lord…

“When referring to a bhikkhu who practises according to Dhamma, this is the proper way of defining ‘practice according to Dhamma.’ When speaking he speaks only Dhamma, not non-Dhamma. When thinking he thinks only thoughts of Dhamma, not thoughts of non-Dhamma. By avoiding these two he lives with equanimity, mindful and clearly comprehending.”

A bhikkhu enjoying the Dhamma
And delighting in the Dhamma,
Reflecting upon the Dhamma,
Does not fall from the true Dhamma.

Whether walking or standing,
Sitting or lying down,
With mind inwardly restrained,
He attains to lasting peace.