The Anthologia Palatina is a collection of Greek poetry, which includes some ancient oracles. This one, translated by W.R. Paton, is #14.75.
An Oracle from Heliopolis
[14.75.1] An oracle given in Heliopolis when the Ship was lost containing the columns of the temple of Zeus there, which are now in Berytus.
[14.75.2] (Zeus is speaking to Apollo)
Tell Poseidon: "Thou shouldst obey thy two elder brethren; it is not meet for thee to glory in the possession of the temples of my glorious palace."
[14.75.3] Say it, and thrice shake the glistening brine, and he will obey. But if he submit not, let him take heed lest I will burn the whole sea; for not even the sea can quench the bolt of Zeus.