Pharaoh told the midwives (Shifrah and Puah) that they should kill every male child that was born. They disobeyed him, as it states (1:17) ֶןֵיהֲלא דִּבֶּר ֶרֲׁשכַּא ׂוָּשע וְלֹא ִיםֱלֹקָאה ֶתא ְיַלְּדֹתַמה ֶ אןִָּירוַתָדִיםַיְלה ֶתא ַ יֶּיןְָּחוַת ָיִםִצְרמ ֶ ךְֶלמ, "The midwives feared Hashem, so they did not do as the king of Mitzrayim had spoken to them. They enabled the boys to live."
They were rewarded for this, as it states (1:21) ִּיםבָּת ֶםָהל ַׂשוַיַּע ִיםֱלֹקָאה ֶתא ְיַלְּדֹתַמה יָרְ אוּ כִּי ִיוַיְה, "Now it took place when the midwives feared Hashem, that He made houses for them."