She Is My Sister
The Hebrew word pronounced aw-khoth means sister, a female with whom one has the same parents (mother and father) or parent (mother or father). The word is found in the Holy Scriptures with the literal physical meaning, but also in the Christian sense whereby true Christians are now conceived, but not yet born, of the same "mother" (i.e. the Church of God, which literally means the people of God, who have within themselves, whether they are male or female, a yet unborn new "self" - see Spiritual Conception) and "Father" - God:
"12:17 And the dragon [see Dragons] was wroth with the woman, and went to make war with the remnant of her seed, which keep the Commandments of God, and have the testimony of Jesus Christ." (Revelation 12:17 KJV)
"She is my sister: for he feared to say, She is my wife"
Abimelech was a Philistine king in Gerar. During a time of famine, Isaac sought refuge for his family there. Fearing that he would be killed by some Philistine who would then claim his wife, Isaac passed Rebekah off as his sister - apparently as his widowed, or otherwise husbandless sister because, if Genesis 25 and 26 are recorded in chronological order, Rebekah was a mother of two children, Jacob and Esau, sometime before then (see Rebekah's Two Nations).
"26:1 And there was a famine in the land, beside the first famine that was in the days of Abraham. And Isaac went unto Abimelech king of the Philistines unto Gerar.
When the Philistines of Gerar discovered the ruse, they scolded Isaac because "one of the people might lightly have lien with thy wife, and thou shouldest have brought guiltiness upon us." Either Isaac was concerned for nothing (not likely), or the Philistines regarded adultery as an executable offense - while making a widow out of a married woman to be acceptable behavior (something that Israelite kings also did e.g. when Nathan The Prophet confronted King David for having Uriah killed so that David could marry Uriah's wife Bathsheba).
"26:8 And it came to pass, when he had been there a long time, that Abimelech king of the Philistines looked out at a window, and saw, and, behold, Isaac was sporting with Rebekah his wife. 26:9 And Abimelech called Isaac, and said, Behold, of a surety she is thy wife: and how saidst thou, She is my sister?
Fact Finder: (a) Was Isaac's calling his wife his sister something that his father Abraham also did? (b) Was Sarah actually Abraham's sister, through one parent?