2 Samuel 20:18

She said: There is an old saying: 'Be sure to seek guidance from Abel before doing anything.' That is the way they settle disputes.

Deuteronomy 20:10-11

When you go to attack a city, first give its people a chance to surrender.

Treasury of Scripture Knowledge

Summary

Then she spake, saying, They were wont to speak in old time, saying, They shall surely ask counsel at Abel: and so they ended the matter.

They were wont, etc

Bible References

They were wont, etc

Deuteronomy 20:10
When you go to attack a city, first give its people a chance to surrender.