16 Heb “Also now, according to your words, so it is.” As the next statement indicates, this does mean that he will do exactly as they say. He does agree with them the culprit should be punished, but not as harshly as they suggest. Furthermore, the innocent parties will not be punished.
17 Heb “The one with whom it is found will become my slave.”
18 The words “the rest of” have been supplied in the translation for clarification and for stylistic reasons.
19 The Hebrew word נָקִי (naqi) means “acquitted,” that is, free of guilt and the responsibility for it. The rest of you will be free. Joseph’s purpose was to single out Benjamin to see if the brothers would abandon him as they had abandoned Joseph. He wanted to see if they had changed.

In other versions

He said, “Let it be as you say: he who is found with it shall be my servant, and the rest of you shall be innocent.”

“Very well, then,” he said, “let it be as you say. Whoever is found to have it will become my slave; the rest of you will be free from blame.”

The steward replied, “What you have said is right, but only the one who is found to have it will be my slave, and the rest of you will be blameless.”

“That’s fair,” the man replied. “But only the one who stole the cup will be my slave. The rest of you may go free.”

Then he said, “Now also according to your words, thus will it be. He who is found with it shall be my slave, but you shall be innocent.”

And he said, Now also let it be according unto your words: he with whom it is found shall be my servant; and ye shall be blameless.

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