16 The particle הִנּוֹ (hinno) is literally, “here he is!” God presents Job to Satan, with the restriction on preserving Job’s life.
17 The has “I deliver him up to you.”
18 Heb “hand.”
19 The irony of the passage comes through with this choice of words. The verb שָׁמַר (shamar) means “to keep; to guard; to preserve.” The exceptive clause casts Satan in the role of a savior—he cannot destroy this life but must protect it.

In other versions

And the Lord said to Satan, “Behold, he is in your hand; only spare his life.”

The Lord said to Satan, “Very well, then, he is in your hands; but you must spare his life.”

“Very well,” the Lord told Satan, “he is in your power; only spare his life.”

“All right, do with him as you please,” the Lord said to Satan. “But spare his life.”

So Yahweh said to Satan, “All right, he is in your power. Only spare his life.”

And the Lord said unto Satan, Behold, he is in thine hand; but save his life.

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