Tang Priest's apprentice was Li Zhi's third son, when Wu Zetian's second son tried to seize power from her. In a rage, Wu Zetian had to abolish him. At this time, the eldest son died, and the third son could only be a prince, and later sat in the dragon chair.

First of all, Tang Priest's apprentice is really Li Zhi's son. At that time, Tang Priest's reputation in the Tang Dynasty was well known after he came back from learning the scriptures. Both Emperor Taizong and Li Zhi respected him very much and kept close contacts. Moreover, at that time, Li Zhi wanted Tang Priest to shave one of his sons, but think about it. The eldest son should be the best in the world, and the second son should be a spare tire. Practice more, just in case, let the third son Li Xian fulfill his wish and become Tang Priest's apprentice.

Secondly, accidents always come suddenly. Li Hong, who was a prince at that time, died of sudden illness without any warning. Li Hong was highly valued, carefully cultivated and held a high position. At that time, his position as a prince was quite stable, and everyone thought he was a suitable candidate. But because of his sudden death, the second prince got the will to inherit the prince.

So, Li Xian is actually a very talented person, but his desire for power is too strong, too sharp-edged. Li Zhi's late health was particularly bad, and he basically couldn't afford to fall ill, but even so, his mother, Wu Zetian, was in power in the DPRK and was an ambitious person. However, Li Xian wanted to compete for this power, so Wu Zetian did not hesitate to abolish his status as a prince.

Finally, in desperation, I can only give this position to Li Xian, who is a leisurely man and won the game.