In Matthew 5:23, Jesus develops his teaching about murderous anger in an unexpected direction. Having stated that anger (v. 22) makes us just as liable to God’s judgment as murder (vv. 21), Jesus’ focus appears to shift in v. 23.

What God had said to Abraham (15:1), he says to his son Isaac. The life of faith involves fearing God rather than people, recognising that he is powerful enough to overcome every obstacle to the fulfilment of his promises.

The sign of the Abrahamic Covenant, the sign of circumcision, was “in your flesh” (Gen. 17:13), where it simultaneously marked God’s extraordinary promise and Abraham’s complete impotency.

Sin is personified by God as a beast crouching at the door, seeking, presumably, to overpower Cain. Just as Adam was tasked with ruling over the beasts of the field, so Cain must rule over sin. In the very next verse it is Cain who rose up against his brother, himself acting with animalistic violence.

There’s a lot to ponder in this passage. And it touches on many present concerns in the church: abuse and safeguarding; truth and falsehood; identity and character. As such, I want to understand it better. And I’d love it if you joined me in my exploration over the next few weeks.