65 The text has Heb “the voices of God.” The divine epithet can be used to express the superlative (cf. Jonah 3:3).
66 The expression וְרַב מִהְיֹת (vérav mihyot, “[the mighty thunder and hail] is much from being”) means essentially “more than enough.” This indicates that the storm was too much, or, as one might say, “It is enough.”
67 The last clause uses a verbal hendiadys: “you will not add to stand,” meaning “you will no longer stay.”

In other versions

Plead with the Lord, for there has been enough of God’s thunder and hail. I will let you go, and you shall stay no longer.”

Pray to the Lord, for we have had enough thunder and hail. I will let you go; you don’t have to stay any longer.”

Make an appeal to the Lord. There has been enough of God’s thunder and hail. I will let you go; you don’t need to stay any longer.”

Please beg the Lord to end this terrifying thunder and hail. We’ve had enough. I will let you go; you don’t need to stay any longer.”

Pray to Yahweh. The thunder of God and hail are enough, and I will release you, and you will no longer have to stay.”

Intreat the Lord (for it is enough) that there be no more mighty thunderings and hail; and I will let you go, and ye shall stay no longer.

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