7887. 'Even on the first day you shall remove yeast from your houses' means that there must be no falsity whatever in good. This is clear from the meaning of the first day' as the beginning of that state, day' being state, see just above in 7881; from the meaning of yeast' as falsity, dealt with below; and from the meaning of house' as good, dealt with in 2233, 2134, 2559, 3652, 3720, 7837-7835, 7848. From these meanings it is evident that 'on the first day you shall remove yeast from your houses' means that from the very beginning of that state there must be no falsity whatever in good. So far as good is concerned, the forms of it are unendingly various; and they derive their specific quality from truths. Consequently the good has the same quality as the truths that enter it. The truths that enter are rarely genuine. Instead they are appearances of truth, and also falsities, though not however opposites of truths. Even so, when these falsities enter good - which happens when a person leads a life in accordance with them - as a result of ignorance, ignorance that has innocence within it, and when the person's end in view is that of doing good, they are regarded by the Lord and in heaven not as falsities but as the equivalents of truth. And according to the character of the person's innocence they are accepted as truths. Such is the way that good obtains its specific quality. From all this one may recognize what is meant by the explanation that there must be no falsity whatever in good.