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 15:24

15:24 then if anything is done unintentionally without the knowledge of the community, the whole community must prepare one young bull for a burnt offering – for a pleasing aroma to the Lord – along with its grain offering and its customary drink offering, and one male goat for a purification offering.