請入朝謝恩 A Summons From The Throne
正悶悶不快，只聽得人叫道：「法師，我等乃比丘國王差來的閣下太宰，特請入朝謝恩也。」八戒笑道：「師父，莫怕，莫怕。正闷闷不快，只听得人叫道：「法师，我等乃比丘国王差来的阁下太宰，特请入朝谢恩也。」八戒笑道：「师父，莫怕，莫怕。
逐句解 Line by line
He was sitting there thoroughly out of sorts when he heard someone calling: "Master of the Law, we are the Grand Preceptors of the Chancellery, sent by the king of Bhikṣu, and we have come expressly to invite you to court to receive his thanks."
法師, Master of the Law, is the formal address for a monk who expounds scripture — a rank above the plain 長老 the king used earlier, and the officials are laying it on. 謝恩 is a precise piece of court language: it means receiving an imperial favour and giving thanks for it, so the invitation is to be thanked and to be grateful for being thanked.
Bajie said with a laugh, "Master, don't be afraid, don't be afraid.
Bajie is the one who works out what is going on, which happens more often than his reputation suggests. The doubled 莫怕 is how the novel writes a person talking someone down — the same repetition it gave the terrified king, used here for comfort instead of panic.
The summons arrives with no explanation attached, which is what makes the next few passages work. Everyone at court knows the crisis is over. Nobody at the hostel does.
Note the honorific inflation. This morning the palace sent an officer in an embroidered coat to drag the Tang Monk out by force; this afternoon it sends Grand Preceptors to invite the Master of the Law. The kingdom's manners track its politics exactly.