Genesis 20:5 continues Abimelech's defense:
"Did he not tell me, She is my sister? and did not she also say, He is my brother? In the truthfulness of my heart and the innocency of my hands have I done this."
Abimelech's argument is airtight. He relied on the testimony of two witnesses — Abraham himself and Sarah herself — both of whom told him, separately, the same story. Any judge in any court would rule for him on those facts alone.
And then he adds the crucial phrase: "In the truthfulness of my heart and the innocency of my hands." The Aramaic of the Targum — bi-q'shitut libbi u-v'nikayut y'day — echoes the Psalmist's language a thousand years later: "He who has clean hands and a pure heart" (Psalm 24:4). Abimelech is making a moral claim and a ritual claim at once. His heart did not intend; his hands did not touch.
The rabbis loved this scene because it complicates an easy reading of the patriarchs. Abraham is not entirely innocent here. He had instructed Sarah to pretend to be his sister, and he had done it twice — first with Pharaoh in Genesis 12 and now with Abimelech. The Targum preserves the awkwardness without excusing it.
Meanwhile, Abimelech — the pagan king, the outsider — speaks with the ethical clarity that the patriarch himself did not always manage. The Torah is comfortable holding both truths at once: the covenant flows through Abraham, but righteousness can sometimes shine brighter in the person outside the covenant than inside it.
The takeaway: honesty of heart and cleanness of hands are the currency that even pagan kings can offer to the God of Israel. And sometimes they offer it more clearly than the patriarchs.