This week's Torah portion, Tzav, focuses on the kohanim (priests) and provides details about the daily mishkan (tabernacle) service. The parsha discusses the various karbanos (offerings) that the kohanim would offer and also mentions that the kohanim must bring offerings with the proper intent. Each offering must be eaten in a state of ritual purity. A couple of other general offerings are also mentioned. One of them, called todah (thanksgiving), is brought when one has experienced a dangerous situation and has come through unharmed: traveling through a desert, sailing on the seas, being released from prison, or recovering from a serious illness.   G-d continues to teach Moses laws relating to the mishkan, including the law of the ner tamid, the constant fire that burned on the altar. Moses performs the lengthy milu'im (consecration) se! rvice of the mishkan, and anoints Aaron and his sons as priests in front of the entire nation, prior to their first service in the mishkan.