Deuteronomy 19:13

19:13 You must not pity him, but purge out the blood of the innocent ¹  from Israel, so that it may go well with you.

[19:13]  ¹ sn Purge out the blood of the innocent. Because of the corporate nature of Israel’s community life, the whole community shared in the guilt of unavenged murder unless and until vengeance occurred. Only this would restore spiritual and moral equilibrium (Num 35:33).