לָמָ֤ה אָמַ֙רְתָּ֙ אֲחֹ֣תִי הִ֔וא וָאֶקַּ֥ח אֹתָ֛הּ לִ֖י לְאִשָּׁ֑ה וְעַתָּ֕ה הִנֵּ֥ה אִשְׁתְּךָ֖ קַ֥ח וָלֵֽךְ׃
Bakit sinabi mong siya'y iyong kapatid, kaya't kinuha ko siya para maging asawa ko? At ngayon, narito ang iyong asawa, kunin mo siya at yumaon ka.”
Rashi
קח ולך TAKE HER AND GO AWAY — Not as Abimelech who said to him (Genesis 20:15) “Behold, my land is before thee; dwell wherever it seemeth proper to thee”: but he (Pharaoh) said to him, “Go and do not stay here,” for the Egyptians are greatly addicted to lewd-living, as it is said. (Ezekiel 23:20). “And whose issue is like the issue of horses” (Midrash Tanchuma, Lech Lecha 5). (The passage deals with the immoral practices of the Egyptians).
Chizkuni
למה אמרת אחותי היא, “why did you say: “she is my sister,” whereas she never said that you are her brother. This is distinctly different from when Sarah had been kidnapped by Avimelech, and the latter had subsequently accused her in his dream of having said that Avraham was her brother. (Genesis 20,5) [It was part of his plea that he was totally innocent. Ed. Our author ascribes Sarah’s conduct vis a vis Pharaoh as due to her relative youth and naivety, whereas by the time she was kidnapped by Avimelech she had become more familiar with the real world.
Ramban
SO THAT I TOOK HER TO BE MY WIFE. The meaning thereof is that it was Pharaoh’s intention that she be his regal wife, not just his concubine. Pharaoh mentioned this to Abraham so that he should confess to him if she is his sister, as I have explained.