Read manga: Crazy, A Three-Year-Old Sect Master?!

Manhua
Summary:

The Sword God Jian ZiQi, proved his way of the sword, cultivated the heavens and practiced his 9 heavenly series and ascended to a golden immortal, but in the secret realm he was ambushed by hundreds of golden immortals, and eventually died. Before he died, Jian ZiQi was able to reincarnate, and was reborn as the 3 year old everlasting sect master!