what un usual favour did emperor to japan extended to gulliver?

The Emperor exempted Gulliver from the act of trampling the crucifix.

"that for the sake of my patron the king of Luggnagg, his majesty would condescend to excuse my performing the ceremony imposed on my countrymen, of trampling upon the crucifix: because I had been thrown into his kingdom by my misfortunes, without any intention of trading."