Shalom. As we have laws for everything, could you please tell me the source for: “one doesn’t have to be a Rabbi (i.e. have a Smichah) to teach Torah” I assume that the same source would state that one must know the subject matter well to teach it. Thank you.
Every father is obligated to teach his children torah, even if he isn’t a Rabbi, as the torah states and we say it in kriyas shema every day, “v’shenantom l’boneicha” “and teach your children”. Shlomo Hamelech also said in Mishlei 31 says “Shema Benei mussar aveicha, v’al titosh toras eimecha”. Listen my son to the mussar of your father and don’t forsake the torah of your mother”. Mothers never have smicha, and neither do most fathers. On the other hand a person may not answer halachic questions unless he is qualified to do so.
Obviously when one teaches he has to know the material well,otherwise he will teach it incorrectly.
Rambam Hilchos Talmud Torah 1-1,2, perek 5- 3,4.