In the tenth and final plague, God struck the firstborn of Egypt, man and beast alike. What is the connection between the slaying of the Egyptian firstborn, and God's command to Israel, to 'sanctify to Me every firstborn?' What does this sanctification mean?

The Torah portion of Bo (Exodus 6 : 2 - 9 : 35) is read on Shabbat, 3 Shevat 5785 - February 1, 2025