Reference for Kiddushin 155:1

זונה משוי לה חללה לא משוי לה חזר ובא עליה עשאה חללה

he renders her zonah, not halalah. But if he again has intercourse with her, he renders her halalah.<span class="x" onmousemove="('comment',' [Since as a result of the first intercourse she becomes forbidden to him also as zonah of the type which is interdicted only to priests.]');">¹</span>

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