Exodus 12:15

Seven days. The first of these seven days was the 15th of the first month (Lev. 23:6; Num. 28:17), or from the evening following the 14th day to the evening following the 21st day of the first month (Ex. 12:18).

Cutoff. There are 36 instances in which an individual who had neglected some particular religious duty, is threatened with being “cut off” from the chosen people. What actually happened in such a case is not known, for no specific instance of such an occurrence is on record, nor were instructions given as to how the threat was to be carried out. Some have thought it meant a violent death, a premature death, or perhaps eternal death. In all probability it simply meant separation from the rights and privileges belonging to an Israelite. After being “cut off” the man was considered a stranger, with no share whatever in the blessings of the covenant.

Though perhaps unknown to others, a man’s misdeed would be known to God, and future compliance with the provisions of ceremonial and moral law would not of itself atone for past sins of omission or commission. The person was disfellowshiped, but whether the act was to be performed by man or by God is not clear. This “cutting off” is probably what Paul makes reference to in Rom. 9:3 (see on Gen. 17:14).