Tafsiran Imamat 15:17: Chizkuni & Ibn Ezra

וְכָל־בֶּ֣גֶד וְכָל־ע֔וֹר אֲשֶׁר־יִהְיֶ֥ה עָלָ֖יו שִׁכְבַת־זָ֑רַע וְכֻבַּ֥ס בַּמַּ֖יִם וְטָמֵ֥א עַד־הָעָֽרֶב׃ (פ)

Setiap pakaian dan setiap barang dari kulit yang terkena air mani harus dicuci dengan air, dan tetap najis sampai petang.

Chizkuni

אשר יהיה עליו שכבת זרע, “(garments or skin) which have been splattered with semen of a human being;” even only partially; (Sifra) just as when this subject was discussed previously it referred to fresh, moist semen, so here too the Torah speaks of freshly emitted semen, not dried out semen.
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Ibn Ezra

It would appear that both one’s skin and one’s clothes require immersion if semen is found on them, whether the semen be wet or dry. However, the truth is in accordance with the received tradition [Nidda 54b].
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