Numbers 5:13

5:13 and a man has sexual relations with her without her husband knowing it, and it is hidden that she has defiled herself, since there was no witness against her, nor was she caught –

Numbers 5:20

5:20 But if you have gone astray while under your husband’s authority, and if you have defiled yourself and some man other than your husband has had sexual relations with you….”

Numbers 6:12

6:12 He must rededicate to the Lord the days of his separation and bring a male lamb in its first year as a reparation offering, but the former days will not be counted because his separation was defiled.

Numbers 9:6-7

9:6 It happened that some men who were ceremonially defiled by the dead body of a man could not keep the Passover on that day, so they came before Moses and before Aaron on that day. 9:7 And those men said to him, “We are ceremonially defiled by the dead body of a man; why are we kept back from offering the Lord’s offering at its appointed time among the Israelites?”

Numbers 9:10

9:10 “Tell the Israelites, ‘If any of you or of your posterity become ceremonially defiled by touching a dead body, or are on a journey far away, then he may observe the Passover to the Lord.