Jing Jiu didn't wear the white cloth. He wore a common cotton robe and put on the conical hat as he usually did.
The broad and large conical hat covered his entire face, and he also employed the Sword Force to protect his appearance. Even if someone looked at his face from under the conical hat, they wouldn't even recognize him.
The reason State Duke Lu could recognize Jing Jiu right away was because he had been thinking about Jing Jiu all this time, and also it was because Jing Jiu had an outstanding aura.
All of a sudden, Jing Jiu disappeared in front of his eyes. State Duke Lu's heart skipped a beat, wondering if his eyes had deceived him because he missed Jing Jiu so much that he became delusional.