Reference for Yevamot 151:9

ואפילו לרבי אלעזר דאמר פנוי הבא על הפנויה שלא לשם אישות עשאה זונה ה"מ איש אבל אשה פריצותא בעלמא:

the action is regarded as mere obscenity. <b><i>MISHNAH</i></b>. A MAN WHO IS WOUNDED IN HIS STONES, AND ONE WHOSE MEMBRUM IS CUT OFF, ARE PERMITTED TO MARRY A PROSELYTE OR AN EMANCIPATED SLAVE. THEY ARE ONLY FORBIDDEN TO ENTER INTO THE ASSEMBLY,<span class="x" onmousemove="('comment',' They may not marry the daughter of an Israelite. ');">²⁰</span> AS IT IS SAID IN SCRIPTURE, HE THAT IS WOUNDED IN HIS STONES OR HATH HIS PRIVY MEMBRUM CUT OFF SHALL NOT ENTER INTO THE ASSEMBLY OF THE LORD.<span class="x" onmousemove="('comment',' Deut. XXIII. 2. ');">²¹</span>

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