15:20 abstain. It was not that these restrictions (any more than circumcision) were required for salvation, but rather for fellowship with the Jerusalem church and with Jewish Christians in general. These practices were all prevalent and characteristic in the pagan world and were particularly offensive to Jews, whether Christian or not, and therefore a real stumbling block. They would also be a real temptation through peer pressure to new Gentile believers and could easily lead them to backslide into paganism if not carefully avoided.
15:20 from blood. Refraining from eating “flesh with the life thereof, which is the blood thereof” (Genesis 9:4; see also Leviticus 17:14) long antedated the laws of Moses. It was part of the ancient Noahic mandate; its restatement here indicates the latter is still in effect (note also Romans 13:1, 4). Furthermore, the primeval dominion mandate given to Adam, which the Noahic mandate merely reconfirmed and extended, is likewise still in effect. This means that Christians are responsible to obey Christ’s primeval command to exercise stewardship over the earth (see notes on Genesis 1:26-28), as well as His great commission to preach the gospel to the uttermost parts of the earth (Acts 1:8).