=Suggestions to the teacher.= A brief review, by question and answer, of the previous lesson, will serve as a point of contact for the story of the sin of the sons of Aaron. Tell how, after the tabernacle had been completed, there was a great celebration continuing for eight days, during which time Moses taught Aaron and his sons, who, as priests, were to perform the sacrifices for the people and in general to lead in the service, exactly what they were to do, when, where and how to kill the animals that were sacrificed, how to make the incense that had to be burnt, how to arrange the shew-bread and prepare the cakes of the meal-offering, etc. On the eighth day God himself, with fire from heaven, lit the wood that had been piled on the altar and thus started the fire there, which the priests were commanded never to let die out, but always to keep burning. Be careful to impress the children with the sinfulness of Nadab and Abihu's conduct, which the bare narrative of the facts as recorded in the Bible will not accomplish. This can be done by suggesting something of the solemnity of the occasion and of the frivolity of their attitude in this wise: "Now Aaron and two of his sons, Eliezer and Ithamar, listened very attentively to all the instructions they had received from Moses and were determined to carry them out exactly. They felt that as priests, chosen from among all the people to lead in the worship of God, it was for them to set an example of faithful obedience to all He said, the small things as well as the great. But the two other sons of Aaron, Nadab and Abihu, felt differently. They, too, were proud of their new office as priests, but instead of feeling that they must lead the people in obedience to God's laws as taught by Moses, they felt that they as priests could do as they pleased with the service and did not have to follow the directions of Moses. So when they were told to burn the incense with fire lit at the flame of the altar that God had kindled, they said to themselves, 'What difference whether we burn the incense with this holy fire or with any other', so they took 'strange fire', that is fire that they themselves had kindled, and brought it into the sanctuary to show that they as priests could perform the service in whatever way they pleased. At this God was very angry. Had an ordinary Israelite disobeyed in some small particular it would not have been as great an offense, but Nadab and Abihu were priests whom God expected to lead the people in obedience and who now had set an example of disobedience on the very day of the dedication of the tabernacle to God's service. It was just as if a teacher had left her class for a time in charge of a monitor whom she trusted, and then found out later that this monitor had himself disobeyed her and had set an example of disobedience to the class in her absence. Do you not think the teacher would be more angry at her monitor than if he