What is the ruling on saying "Jesus" out of wonder or astonishment, and does that fall under polytheism (shirk)?

It is not permissible for a Muslim to say "Jesus" when surprised or frightened, for two reasons:

1. Imitating disbelievers, which is forbidden due to the Prophet's (peace and blessings be upon him) saying: "Whoever imitates a people is one of them."

2. It is a supplication to and seeking aid from 'Isa (Jesus), peace be upon him, and this is polytheism with Allah the Almighty. Allah the Almighty said: "And do not invoke besides Allah that which neither benefits you nor harms you, for if you did, then indeed you would be among the wrongdoers." And Allah the Almighty forbade the Companions from saying "Ra'ina" because the Jews intended an ugly meaning by it.