The Rebbe sends blessings in connection with 12–13 Tammuz and responds to previous letters. He acknowledges receipt of Le’or HaHalachah with thanks and brief notes, discusses assisting someone in need, and shares concise halachic insights on warfare, sale of chametz, and the debate between Beit Shammai and Beit Hillel.
https://www.torahrecordings.com/rebbe/igroskodesh/015/011/5604