When ye be come into the land of Canaan, which I give to you for a possession, and I {l} put the plague of leprosy in a house of the land of your possession;

(l) This declares that no plague nor punishment comes to man without God's providence and his sending.

Jamieson-Fausset-Brown Bible Commentary

34-48. leprosy in a house-This law was prospective, not to come into operation till the settlement of the Israelites in Canaan. The words, "I put the leprosy," has led many to think that this plague was a judicial infliction from heaven for the sins of the owner; while others do not regard it in this light, it being common in Scripture to represent God as doing that which He only permits in His providence to be done. Assuming it to have been a natural disease, a new difficulty arises as to whether we are to consider that the house had become infected by the contagion of leprous occupiers; or that the leprosy was in the house itself. It is evident that the latter was the true state of the case, from the furniture being removed out of it on the first suspicion of disease on the walls. Some have supposed that the name of leprosy was analogically applied to it by the Hebrews, as we speak of cancer in trees when they exhibit corrosive effects similar to what the disease so named produces on the human body; while others have pronounced it a mural efflorescence or species of mildew on the wall apt to be produced in very damp situations, and which was followed by effects so injurious to health as well as to the stability of a house, particularly in warm countries, as to demand the attention of a legislator. Moses enjoined the priests to follow the same course and during the same period of time for ascertaining the true character of this disease as in human leprosy. If found leprous, the infected parts were to be removed. If afterwards there appeared a risk of the contagion spreading, the house was to be destroyed altogether and the materials removed to a distance. The stones were probably rough, unhewn stones, built up without cement in the manner now frequently used in fences and plastered over, or else laid in mortar. The oldest examples of architecture are of this character. The very same thing has to be done still with houses infected with mural salt. The stones covered with the nitrous incrustation must be removed, and if the infected wall is suffered to remain, it must be plastered all over anew.

Matthew Henry's Concise Commentary

14:33-53 The leprosy in a house is unaccountable to us, as well as the leprosy in a garment; but now sin, where that reigns in a house, is a plague there, as it is in a heart. Masters of families should be aware, and afraid of the first appearance of sin in their families, and put it away, whatever it is. If the leprosy is got into the house, the infected part must be taken out. If it remain in the house, the whole must be pulled down. The owner had better be without a dwelling, than live in one that was infected. The leprosy of sin ruins families and churches. Thus sin is so interwoven with the human body, that it must be taken down by death.