Roughly speaking, the meaning is: I, Li Jing, have some status in Nantang. Back then, my rebellion was forced by Master Wen; it was to protect my family, and I had no intention of opposing Yin Shang. I've always been watching what you've done. Now that you're in a desperate situation, why not join Nantang and make yourself useful? That way, you might still achieve something in the future.
Zhang Guifang was quite moved upon receiving the letter. What kind of status does Li Jing hold in Nantang?
His trusted aide chimed in, saying, "General, Heavenly King Li is so righteous and sincere. Why not submit to him?"
How could Zhang Guifang not know his subordinates' sentiments?
Still, he replied with one condition: he would not act against Yin Shang.
Li Jing agreed without hesitation, thinking to himself, "If you're not fighting Yin Shang, then go battle the barbarians. Either way, you're working for Nantang."