Does lifting the knife while slaughtering an animal, then returning it to complete the slaughter, render the animal unlawful to eat?

If the slaughterer lifts his hand during the slaughter and immediately returns it, the animal is permissible to eat. However, if there is a long interval, it is not permissible to eat. What constitutes "near" and "far" is determined by custom. If the slaughterer severs some vital organs, such as cutting some of the jugular veins, and then returns immediately, the animal is permissible to eat. If he has not severed them, meaning if left, the animal would live, then it is permissible to eat in all cases, whether he returned after a short or long interval, because it is considered an independent slaughter at that point.