Leviticus 15:18
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.
Cross-reference
Leviticus 15:5
Parallel
In Leviticus 15:5, the same purification rule applies to touching the bed—both require bathing and evening uncleanness.
Exodus 19:15
Parallel
Exodus 19:15 commands abstinence to approach God, directly paralleling the uncleanness from intercourse here.
1 Samuel 21:5
Allusion
1 Samuel 21:5 continues David's defense, affirming holiness by abstaining from women, echoing this verse's uncleanness.