Numbers 35:21 Kabbalah

א֣וֹ בְאֵיבָ֞ה הִכָּ֤הוּ בְיָדוֹ֙ וַיָּמֹ֔ת מֽוֹת־יוּמַ֥ת הַמַּכֶּ֖ה רֹצֵ֣חַֽ ה֑וּא גֹּאֵ֣ל הַדָּ֗ם יָמִ֛ית אֶת־הָרֹצֵ֖חַ בְּפִגְעוֹ־בֽוֹ׃

or in enmity smote him with his hand, that he died; he that smote him shall surely be put to death: he is a murderer; the avenger of blood shall put the murderer to death when he meeteth him.

Read kabbalistic (mystical) interpretation of Numbers 35:21: and classical mystical sources.