Pasting the 福 (fú) character, especially during the Spring Festival (Chinese New Year), is one of the most widespread and important customs in Chinese culture.
1. Meaning of 福 (Fú):
The character 福 (fú) itself is rich with meaning. It represents good fortune, blessing, happiness, and prosperity. It is a wish for all that is good in the coming year.
The character is often deconstructed:
The left radical 示 (shì) signifies "spirit" or "to show," relating to divine matters.
The right side 畐 (fú) represents "a full vessel," symbolizing abundance and fulfillment.
So, literally, it means the spiritual manifestation of abundance.
2. How It's Done:
Timing: The couplets (春联, chūnlián) and the 福 character are traditionally pasted on the door on New Year's Eve, after cleaning the house and before the family reunion dinner. This act seals in the good luck for the incoming year.
Placement: The 福 is pasted on doors (main door, room doors), windows, and walls around the home.
3. The Inversion - Upside Down Fu (福倒了 - Fú Dào Le):
The Most Important Detail: You will very often see the 福 character pasted upside down.
Why? This is a deliberate and cherished pun. The word for "upside down" or "to arrive" is 倒 (dào).
Punning Meaning: So, 福倒了 (Fú dào le) sounds identical to 福到了 (Fú dào le), which means "Good fortune has arrived." or "Blessings are upon us."
Context: In your story, the fact that Grandpa Jing is doing this before leaving on a migration is incredibly poignant. It's a powerful act of hope—a way to literally usher in and invoke good luck for a dangerous and uncertain journey ahead. They are taking their blessings with them in spirit.
4. Connection to Spring Festival Couplets (春联 - Chūnlián):
The 福 character is closely related to the couplets (春联). The couplets are poetic lines written on red paper, placed vertically on either side of the door. They express hopes for prosperity, health, and happiness in the new year. A horizontal scroll, often with a phrase like 吉祥如意 (Jíxiáng rúyì - "Good luck according to your wishes"), is placed above the doorframe. The 福 character is often pasted in the center of the door or on windows to complete the display.