Psalms 105:36 Midrash

וַיַּ֣ךְ כָּל־בְּכ֣וֹר בְּאַרְצָ֑ם רֵ֝אשִׁ֗ית לְכָל־אוֹנָֽם׃

He smote also all the first-born in their land, The first-fruits of all their strength.

Read midrashic interpretation of Psalms 105:36: and classical rabbinic exegesis.