73 This verb is future indicative, and thus not subordinate to “grant” (διατίθεμαι, diatithemai) as part of the result clause beginning with ἵνα ἕσθητε (hina esthēte) at the beginning of v. 30. It is better understood as a predictive future.
74 The statement you will sit on thrones judging the twelve tribes of Israel looks at the future authority the Twelve will have when Jesus returns. They will share in Israel’s judgment.

In other versions

that you may eat and drink at my table in my kingdom and sit on thrones judging the twelve tribes of Israel.

so that you may eat and drink at my table in my kingdom and sit on thrones, judging the twelve tribes of Israel.

so that you may eat and drink at my table in my kingdom. And you will sit on thrones judging the twelve tribes of Israel.

to eat and drink at my table in my Kingdom. And you will sit on thrones, judging the twelve tribes of Israel.

that you may eat and drink at my table in my kingdom, and you will sit on thrones judging the twelve tribes of Israel.

That ye may eat and drink at my table in my kingdom, and sit on thrones judging the twelve tribes of Israel.

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