望空禮拜 Bowing To The Empty Sky
真人笑道：「不勞，不勞。」遂長揖一聲，騰空而去。慌得那皇帝、皇后及大小眾臣，一個個望空禮拜。真人笑道：「不劳，不劳。」遂长揖一声，腾空而去。慌得那皇帝、皇后及大小众臣，一个个望空礼拜。
逐句解 Line by line
The Perfected Man laughed and said, "No trouble, no trouble."
Eight characters, attribution and closing quotation both inside, so it stands alone. 不 keeps bù before the rising tone of 勞, twice.
Then he made a long bow, and rose into the air and was gone.
長 is cháng here — a 長揖 is a deep bow made standing, hands clasped and arms swept from high to low. The same character is zhǎng in 長老 and cháng again in 長壽, three different jobs in one chapter.
That threw the emperor, the queen and all the officials great and small into a flurry, and one and all they bowed to the empty sky.
得 is de, the light link between the startlement and what it produced. 一 takes yí before the falling tone of 個.
不勞，不勞 — no trouble, no trouble — is the whole of his response to being offered a royal audience. He came, undid three years of enchantment with one gesture, declined the thanks, bowed and left. The novel gives him about a hundred characters of dialogue in total.
長揖 is a specific bow: made standing rather than kneeling, hands clasped, arms swept down from above the head. It is the bow of an equal or a superior, not a subject — appropriate for an immortal leaving a mortal court, and pointedly not the prostration everybody else in the chapter has been making.
The last image is the court bowing at nothing. 望空禮拜 — they perform the reverence towards empty sky, because he has already gone. Everybody in the hall is thanking somebody who is not there, which is roughly what the whole chapter has been doing.