וְהָיָ֗ה כִּֽי־יִרְא֤וּ אֹתָךְ֙ הַמִּצְרִ֔ים וְאָמְר֖וּ אִשְׁתּ֣וֹ זֹ֑את וְהָרְג֥וּ אֹתִ֖י וְאֹתָ֥ךְ יְחַיּֽוּ׃
And it will come to pass, when the Egyptians shall see thee, that they will say: This is his wife; and they will kill me, but thee they will keep alive.
Read kabbalistic (mystical) interpretation of Genesis 12:12: and classical mystical sources.