Truth and Lies

Kids in camp often ask counselors when color war will be, and they often respond that they don’t know, when they actually do. Does this violate the prohibition of lying?

May I take credit for something that I did not do myself? Must I make a full disclosure when it may cause a negative outcome? Is it permitted to “add” to the truth?

The student who tricked his Rav that he was listening to the zoom lesson...

If someone asks me for an answer during a test, can I tell him the wrong answer?

A Yeshiva student tricked the guy that he is sick with a Contagoues sickness so that he could learn quietly.