Question: Must one be careful regarding the Kashrut standards of the foods one’s children eat as well?
Answer: Regarding any food which is prohibited for consumption by the Torah, such as milk and meat or an impure animal’s milk, it is certainly forbidden to give such foods to children, even if they are only infants. It is indeed a Torah prohibition to feed children non-kosher meat or any other food prohibited by the Torah. The question remains regarding foods which are not forbidden by an actual Torah prohibition but only raise Kashrut concerns, such as milk whose origin is unknown, in which case there is room to say that most milk comes from pure animals and ascertaining the fact that it is indeed so is only a rabbinic law. In such a case, it will be permissible to feed such an item to a child when necessary. Similarly, regarding sweets which may not be under superior Kashrut supervision and there may be room to act leniently and eat them, nevertheless, adults customarily abstain from eating such things. The question is, is there room for stringency with regards to children as well?
The holy Torah writes, “Do not repulse your souls by (consuming) any crawling creatures and you shall not become impure through them, for they shall cause you to be impure.” Our Sages expound this verse to mean that when one consumes forbidden foods, one’s heart becomes spiritually blocked and a holy spirit cannot rest upon the individual (Yoma 39a). The Gemara in Masechet Yoma (80a) states that when one impurifies himself slightly (by consuming forbidden foods), one is impurified even more from Above.
The Talmud Yerushalmi states that an infant may nurse from a non-Jewish woman and this is not prohibited at all. It seems from the Yerushalmi that there is not even room for stringency and this is completely permissible. The Rishonim nevertheless write that one should not do so unless one has no other choice. Indeed, the Rashba writes that Jews are naturally bashful and merciful and by nursing from a non-Jew, this will cause the baby to develop a cruel and brazen nature. His student, the Ritba, adds that the milk of a non-Jewish woman who consumes all sorts of insects and repulsive creatures will cause a bad and cruel nature to enter the child. The source of this matter is based on what our Sages taught that eating forbidden foods causes the individual’s heart to be spiritually blocked and a spirit of purity will not be able to enter him and he will not be able to absorb matters of holiness.
Based on this, even when something is completely permissible, nevertheless since it may cause spiritual blockage of the heart, one should be careful and abstain from consuming it. Every Jew wishes to see his children grow up to follow the true path of the Torah, but through a lack of concern regarding forbidden foods, one can bring great evil upon one’s sons or daughters by strengthening their hearts until it resembles a heart of stone, which will, G-d-forbid, be incapable of heeding the Torah.
It is therefore truly worthy to be stringent and not allow even young children to eat any food which poses a Kashrut concern. By doing so, one will merit seeing a spirit of purity resting upon them like their other holy Jewish brethren.