Hello Rabbi, What is the commandment against lying and what does it entail? Best

ב"ה Shalom The prohibition of lying is explicit in the Torah, in Shemot 23:7 "Keep away from anything false" which includes the speaking of lies. There are long discussions among the commentators: Does the prohibition of lying apply only if damage is caused by the lie to another person's reputation, or if monetary loss is caused as a result of the lie, or just the very telling of a lie, so it is difficult to get into all those details with you asking about a specific circumstance. Also, in our world today with all the social media which gets around so quick, telling a lie can entail a lot than just the lie, there is the shaming and besmirching and so much more. All the best