儒释道

Standard shorthand for the 三教 ('Three Teachings') — Confucianism (儒), Buddhism (释, after 释迦牟尼 'Shakyamuni'), and Daoism (道). Buddhism arrived from India in the Han dynasty and by the Tang had been thoroughly Sinicized, sharing temple space and even deities with the other two. The Ming-Qing slogan 三教合一 ('the three teachings are one') captures the resulting syncretism.

Note 释 here means 'Shakyamuni / Buddhism' (not its usual meaning 'release, explain') — Chinese Buddhists historically took 释 as a surname, e.g. 释一行 (Tang astronomer-monk).