"And when the zav is cleansed from his discharge... And on the eighth day, he shall take for himself two turtledoves..."—Leviticus 15:13-14.
A man who is a zav [one who suffers an abnormal seminal discharge] must, after the disorder has been cured, bring an offering—two pigeons or two turtledoves, one as a Burnt Offering and one as a Sin Offering.
Until he brings this offering, his purification process is not complete and he may not partake of sacrificial flesh.