OP: 'Pain is inevitable. Suffering is optional.'

I am quoting the viewpoint of the Theravada school which agrees with this statement, and I've never heard of another school disagreeing with this statement.

According to Itivuttaka 44, enlightened ones can still feel pain and pleasure:

"What, bhikkhus, is the Nibbana-element with residue left? Here a bhikkhu is an arahant, one whose taints are destroyed, the holy life fulfilled, who has done what had to be done, laid down the burden, attained the goal, destroyed the fetters of being, completely released through final knowledge. However, his five sense faculties remain unimpaired, by which he still experiences what is agreeable and disagreeable and feels pleasure and pain. It is the extinction of attachment, hate, and delusion in him that is called the Nibbana-element with residue left.

However, the enlightened ones don't suffer, even when they feel pain (from DN16):

And soon after the Blessed One had eaten the meal provided by Cunda the metalworker, a dire sickness fell upon him, even dysentery, and he suffered sharp and deadly pains. But the Blessed One endured them mindfully, clearly comprehending and unperturbed.

Also see this answer.

In the Nakulapita Sutta:

"So it is, householder. So it is. The body is afflicted, weak, & encumbered. For who, looking after this body, would claim even a moment of true health, except through sheer foolishness? So you should train yourself: 'Even though I may be afflicted in body, my mind will be unafflicted.' That is how you should train yourself."

OP: 'Pain is inevitable. Suffering is optional.'

I am quoting the viewpoint of the Theravada school which agrees with this statement, and I've never heard of another school disagreeing with this statement.

According to Itivuttaka 44, enlightened ones can still feel pain and pleasure:

"What, bhikkhus, is the Nibbana-element with residue left? Here a bhikkhu is an arahant, one whose taints are destroyed, the holy life fulfilled, who has done what had to be done, laid down the burden, attained the goal, destroyed the fetters of being, completely released through final knowledge. However, his five sense faculties remain unimpaired, by which he still experiences what is agreeable and disagreeable and feels pleasure and pain. It is the extinction of attachment, hate, and delusion in him that is called the Nibbana-element with residue left.

However, the enlightened ones don't suffer, even when they feel pain or are deprived of pleasure (from DN16):

And soon after the Blessed One had eaten the meal provided by Cunda the metalworker, a dire sickness fell upon him, even dysentery, and he suffered sharp and deadly pains. But the Blessed One endured them mindfully, clearly comprehending and unperturbed.

Also see this answer.

In the Nakulapita Sutta:

"So it is, householder. So it is. The body is afflicted, weak, & encumbered. For who, looking after this body, would claim even a moment of true health, except through sheer foolishness? So you should train yourself: 'Even though I may be afflicted in body, my mind will be unafflicted.' That is how you should train yourself."

OP: 'Pain is inevitable. Suffering is optional.'

I am quoting the viewpoint of the Theravada school which agrees with this statement, and I've never heard of another school disagreeing with this statement.

According to Itivuttaka 44, enlightened ones can still feel pain and pleasure:

"What, bhikkhus, is the Nibbana-element with residue left? Here a bhikkhu is an arahant, one whose taints are destroyed, the holy life fulfilled, who has done what had to be done, laid down the burden, attained the goal, destroyed the fetters of being, completely released through final knowledge. However, his five sense faculties remain unimpaired, by which he still experiences what is agreeable and disagreeable and feels pleasure and pain. It is the extinction of attachment, hate, and delusion in him that is called the Nibbana-element with residue left.

However, the enlightened ones don't suffer, even when they feel pain and pleasure (from DN16):

And soon after the Blessed One had eaten the meal provided by Cunda the metalworker, a dire sickness fell upon him, even dysentery, and he suffered sharp and deadly pains. But the Blessed One endured them mindfully, clearly comprehending and unperturbed.

Also see this answer.

In the Nakulapita Sutta:

"So it is, householder. So it is. The body is afflicted, weak, & encumbered. For who, looking after this body, would claim even a moment of true health, except through sheer foolishness? So you should train yourself: 'Even though I may be afflicted in body, my mind will be unafflicted.' That is how you should train yourself."

OP: 'Pain is inevitable. Suffering is optional.'

I am quoting the viewpoint of the Theravada school which agrees with this statement, and I've never heard of another school disagreeing with this statement.

According to Itivuttaka 44, enlightened ones can still feel pain and pleasure:

"What, bhikkhus, is the Nibbana-element with residue left? Here a bhikkhu is an arahant, one whose taints are destroyed, the holy life fulfilled, who has done what had to be done, laid down the burden, attained the goal, destroyed the fetters of being, completely released through final knowledge. However, his five sense faculties remain unimpaired, by which he still experiences what is agreeable and disagreeable and feels pleasure and pain. It is the extinction of attachment, hate, and delusion in him that is called the Nibbana-element with residue left.

However, the enlightened ones don't suffer, even when they feel pain (from DN16):

And soon after the Blessed One had eaten the meal provided by Cunda the metalworker, a dire sickness fell upon him, even dysentery, and he suffered sharp and deadly pains. But the Blessed One endured them mindfully, clearly comprehending and unperturbed.

Also see this answer.

In the Nakulapita Sutta:

"So it is, householder. So it is. The body is afflicted, weak, & encumbered. For who, looking after this body, would claim even a moment of true health, except through sheer foolishness? So you should train yourself: 'Even though I may be afflicted in body, my mind will be unafflicted.' That is how you should train yourself."