Leviticus 15:3

And this is the law of his uncleanness for a discharge : whether his body runs with his discharge , or his body is blocked up by his discharge , it is his uncleanness .

Whether it continues flowing from his body or is blocked, it will make him unclean. This is how his discharge will bring about uncleanness:

And this shall be his uncleanness in his issue : whether his flesh run with his issue, or his flesh be stopped from his issue, it is his uncleanness.