In which excerpt does Sir Gawain display honesty and modesty by publicly acknowledging his failings in Authur's court?

If the excerpt is,

If I without discourtesy might quit this board,

And if my liege lady misliked it not,

I would come to your counsel before your court noble.

For I find it not fit, as in faith it is known,

When such a boon is begged before all these knights ...

"She guided me in this guise to your glorious hall,

To assay, if such it were, the surfeit of pride

That is rumored of the retinue of the Round Table.

She put this shape upon me to puzzle your wits, ...

"Behold, sir," said he, and handles the belt,

"This is the blazon of the blemish that I bear on my neck;

This is the sign of sore loss that I have suffered there;

For the cowardice and coveting that I came to there;

This is the badge of false faith that I was found in there, ...

"No, by God," said Sir Gawain, "that granted me life,

I shall grudge not the guerdon, grim though it prove;

Bestow but one stroke, and I shall stand still,

And you may lay on as you like till the last of my part

be paid."

Then the answer would be "Behold, sir," said he, and handles the belt,

"This is the blazon of the blemish that I bear on my neck;

This is the sign of sore loss that I have suffered there;

For the cowardice and coveting that I came to there;

This is the badge of false faith that I was found in there, ...