'Mediator' in the Bible
All these [men] were the sons of Heman the king’s seer to exalt him in accordance with the words of God; for God gave Heman fourteen sons and three daughters.
Now the mediator or go-between [in a transaction] is not [needed] for just one party; whereas God is only one [and was the only One giving the promise to Abraham, but the Law was a contract between two, God and Israel; its validity depended on both].
in every situation [no matter what the circumstances] be thankful and continually give thanks to God; for this is the will of God for you in Christ Jesus.
For there is [only] one God, and [only] one Mediator between God and mankind, the Man Christ Jesus,
But as it is, Christ has acquired a [priestly] ministry which is more excellent [than the old Levitical priestly ministry], for He is the Mediator (Arbiter) of a better covenant [uniting God and man], which has been enacted and rests on better promises.
For this reason He is the Mediator and Negotiator of a new covenant [that is, an entirely new agreement uniting God and man], so that those who have been called [by God] may receive [the fulfillment of] the promised eternal inheritance, since a death has taken place [as the payment] which redeems them from the sins committed under the obsolete first covenant.
and to Jesus, the Mediator of a new covenant [uniting God and man], and to the sprinkled blood, which speaks [of mercy], a better and nobler and more gracious message than the blood of Abel [which cried out for vengeance].