A baal Teshuva who does not speak English well was preparing an apple pie and bought (has veshalom) lard (hog fat) thinking that the crown on the label means it was kosher margarine. She prepared the pie in electric oven on a stone and served it for Shabbat. Can one remedy this sin? When the Temple stood was chatat and asham offered, is there a fast one must undertake? Can the knife, glass and metal kitchen aids be koshered or must they be thrown away? Can the oven be koshered by broiling it 2 hours? In addition to halacha are there remedies for this sin of eating forbidden substance? Than you.
1. Concerning the sin of eating forbidden foods, this was done inadvertantly, and although it is a sin repentance itself helps. You can accept a fast upon yourself if you feel this will help you to find deeper regret, but there is no obligation to do so. In times of the Temple you would, indeed, bring an offering, but today this is not an option, and you need not worry beyond the process of repentance.
2. The kitchen aids can be kashered. Utensils that were in contact with the food can be kashered by means of immersion in boiling (bubbling) water; those that came into contact with the food in conjunction with a heat source (in the oven) must undergo libbun (kashering by means of fire), which is not possible for glass.
3. If the oven is a self-cleaning oven the cleaning cycle is sufficient. If not, it should be cleaned thoroughly and left on at the highest temperature for an hour. The case at hand is more lenient than most, because it is a solid pie that doesn’t affect the walls of the oven. The process above is therefore a stringency in this case.