Though The Mind Is Free
Though the mind of the arahant is free from defilements, his body is still subject to decay, disease and injury, to pain and discomfort.
He can overcome these by inducing supramundane consciousness, which is always at his disposal, but it would be impracticable for him to do so for any length of time.
Therefore, during life, the arahant can enjoy only an intermittent release from suffering. This is called sa-upaadi-sesa-nibbaana, nibbaana with the groups of existence still remaining, since he still exists as an individualized personality subject to the results of residual karma.
Thus, the Buddha met a foot injury when Devadatta hurled a rock at him, the Venerable Mahaa Moggallaana was battered to death by professional criminals, and the Venerable Angulimaala was hit by sticks and stones while on his alms round.