Reference for Niddah 67:2

(שופטים כ, יא) ויאסף כל איש ישראל אל העיר כאיש אחד חברים הכתוב עשאן כולן חברים

during a festival the Rabbis treated as clean; for it is written, So all the men of Israel were gathered again against the city, knit together<span class="x" onmousemove="('comment',' Haberim, plural of haber. ');">²</span>

Jastrow