'Mutually' in the Bible

The king, his princes, and the entire assembly in Jerusalem had mutually decided to observe the Passover in the second month,

“I will make those who oppress you consume their own flesh [in mutually destructive wars]And they will become drunk with their own blood as with sweet wine;And all mankind will know [with a knowledge grounded in personal experience] that I, the Lord, am your SaviorAnd your Redeemer, the Mighty One of Jacob.”

that is, to be mutually encouraged by each other’s faith, both yours and mine.

so we, who are many, are [nevertheless just] one body in Christ, and individually [we are] parts one of another [mutually dependent on each other].