Leviticus 15:18

16 And if any man’s seed of copulation go out from him, then he shall wash all his flesh in water, and be unclean until the even.

17 And every garment, and every skin, whereon is the seed of copulation, shall be washed with water, and be unclean until the even.

The woman also with whom man shall lie with seed of copulation, they shall both bathe themselves in water, and be unclean until the even.

19 And if a woman have an issue, and her issue in her flesh be blood, she shall be put apart seven days: and whosoever toucheth her shall be unclean until the even.

20 And every thing that she lieth upon in her separation shall be unclean: every thing also that she sitteth upon shall be unclean.

This was said to Israel at a particular time, so it is wise to read it together with the surrounding text. Do read the surrounding verses too, because the context often says more than a single verse.

Compare

BSB
If a man lies with a woman and there is an emission of semen, both must bathe with water, and they will remain unclean until evening.
KJV
The woman also with whom man shall lie with seed of copulation, they shall both bathe themselves in water, and be unclean until the even.
WEB
If a man lies with a woman and there is an emission of semen, they shall both bathe themselves in water, and be unclean until the evening.
ASV
The woman also with whom a man shall lie with seed of copulation, they shall both bathe themselves in water, and be unclean until the even.
DARBY
And a woman with whom a man lieth with seed of copulation they shall bathe in water, and be unclean until the even.
BLB
And a woman that a man lies with, [and there is] seed [from] lying, then they shall bathe in the water, and they be unclean until the evening.
ÅB
Og når en mann ligger hos en kvinne, og det går sæd fra ham, da skal de begge bade seg i vann og være urene til om kvelden.
OTB
Hvis en mann har samleie med en kvinne og det er en sædavgang, må begge bade i vann og være urene til kvelden.
B1930
Og når en mann ligger hos en kvinne, og det går sæd fra ham, da skal de begge bade sig i vann og være urene til om aftenen.

Study notes (Tyndale)

Original text and word study

Cross references