אֵ֚לֶּה קריאי [קְרוּאֵ֣י] הָעֵדָ֔ה נְשִׂיאֵ֖י מַטּ֣וֹת אֲבוֹתָ֑ם רָאשֵׁ֛י אַלְפֵ֥י יִשְׂרָאֵ֖ל הֵֽם׃
These were the elect of the congregation, the princes of the tribes of their fathers; they were the heads of the thousands of Israel.
Read kabbalistic (mystical) interpretation of Numbers 1:16: and classical mystical sources.