[ At Saavatthii the Blessed One said: ] "Monks, I will explain to you grasping and worrying, and also not grasping and not worrying... Here, monks, the uninstructed worldling, with no regard for Noble Ones, [1] unskilled and untrained in the Dhamma of the Noble Ones,... of those who are worthy [2] ... regards body as the self, the self as having body, body as being in the self, or the self as being in the body. Change occurs to this man's body, and it becomes different. Because of this change and alteration in his body, his consciousness is preoccupied with bodily change. Due to this preoccupation with bodily change, worried thoughts arise and persist, laying a firm hold on his mind. Through this mental obsession he becomes fearful and distressed, and being full of desire [3] and attachment he is worried. He regards feeling as the self,... change occurs to his feeling... he is worried. [ Similarly with 'perception,' 'the mental formations' and 'consciousness']. In this way, monks, grasping and worrying arise. And how, monks, do not grasping and not worrying arise?
"Here, monks, the well-instructed Ariyan disciple, who has regard for the Noble Ones, is skilled and trained in the Dhamma of the Noble Ones,... of those who are worthy, does not regard body as the self, the self as having body, body as being in the self, or the self as being in the body. Change occurs to this man's body, and it becomes different, but despite this change and alteration in his body, his consciousness is not preoccupied with bodily change... Not being full of desire and attachment, he is not worried. [ Similarly with 'feeling,' 'perception,' 'the mental formations' and 'consciousness']. In this way, monks, grasping and worrying do not arise."