Reference for Arakhin 11:2

עובד כוכבים שהתנדב נדבה לבדק הבית מקבלים הימנו ותניא אידך

Said R'Ela in the name of R'Johanan: This is no difficulty: The first applies to the beginning,<span class="x" onmousemove="('comment',' At the beginning of the building the intention of the idol-worshippers may not be a good one, their gift being made to give them entry into the building programmed which they plan to interfere with or delay. But according to the law they may be accepted for Temple repairs, hence the ruling of R. Judah.');">¹</span>

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