It occurred to scientists only about 30 years ago that insect pests might be controlled through hormones. If, for example, a hormone that prevented a destructive insect from reaching maturity was applied to a crop, the interrupted life cycle of the insect might prevent damage to the crop. Yet the hormone would be a safe, natural substance.
Leviticus 4:20–35 seem to teach that animal sacrifices can take away sins, while Hebrews 10:4–11 reveal they did not. Ron Dudek explains.
Problem: The book of Leviticus discusses many of the sacrifices performed by the Levitical priests. In some places, it seems to claim that a particular offering could remove sins.
And he shall do with the bull as he did with the bull as a sin offering; thus he shall do with it. So the priest shall make atonement for them, and it shall be forgiven them. (Leviticus 4:20)
Yet the book of Hebrews explicitly states that animal blood could not take away sins.
For it is not possible that the blood of bulls and goats could take away sins. (Hebrews 10:4)