Judah sends the goat back down with his servant - and guess who's not there? The prostitute! We've got a prostitute running around Israel with his Power of Attorney. Can you imagine the feeling in his gut?
It gets worse... She gets pregnant by this encounter; and four months later you can't hide it anymore, so the people come to Judah, and they say: Judah, your daughter is pregnant by prostitution. What do you say we do to her? He says: burn her at the stake.
They bring her out to burn her at the stake; and like any good feminist, Tamar goes: excuse me, before we go burning anybody... I've got a ring, and whoever's ring this belongs to is the dad - and it was Judah's ring! So Judah lets her off the hook - because he'd have to burn himself.
It gets worse. She's not just pregnant with one baby, she's pregnant with two – twins! Perez won the wrestling match, and pulled the firstborn's arm back in the womb. Why would they put that in Jesus' genealogy?
The firstborn had to be the judge for the whole family. Because of that, they also had to be the judged; they were responsible for the sin of their whole family. If I'm the firstborn, and my little brother kills somebody, and he makes it to a city of refuge - they could still come get me!
In order to be the judge, you also have to be the judged; to be willing to take the justice. Jesus is the only judge, because He became the firstborn for all creation. He's also the judged: He took the justice.
In the first Adam you get justice, but in the second Adam you get mercy - that's what it means to be ‘born-again’. I have been moved from a position of Justice, to a position of Mercy. You now have a firstborn who is responsible for your sin
The one with the legal right to mercy, took the form of justice, in order to become the firstborn for all creation. If Jesus is your firstborn, then you're the second born; He takes the Justice; you get the Mercy.
"She hath been more righteous than I" Gen 38.26
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