There were many situations where a first century Christian or Jew may have encountered meat sacrificed to idols.
Meat was offered to idols before being served in temples’ dining halls
(often as part of worship) or being used for communal meals; some of
the meat served at the marketplace had been offered to idols. One who
ate in a temple would know the source of the meat; one who ate at a
pagan friend’s home could never be certain. In pagan cities with large
Jewish populations, Jews normally had their own markets.
Palestinian Jewish teachers debated what to do in many cases of
uncertainty (such as untithed food), but would never have taken a
chance on food that might have been offered to an idol. They believed
that Jews outside Palestine unwittingly compromised with idolatry when
invited to pagans’ banquets for their sons, even if they brought their
own food. Following such teachings strictly (as some did) would have
greatly circumscribed their relationships with pagan colleagues. The
matter was more troubling for Christians converted from pagan
backgrounds: could they meet over lunch with business associates or
fellow members of their trade guild, or attend a reception in a temple
for a relative’s wedding?
In chapters 8–10, Paul works on an elaborate compromise between two
factions in the Corinthian church. The more educated and socially
elite group, who unlike the poor ate meat regularly and not just when
it was doled out at pagan festivals, had well-to-do friends who would
serve meat. They probably represent the liberal faction, who consider
themselves “strong” and the socially lower group “weak.”1
Of course if the Christians themselves were sacrificing to idols this is another issue altogether which is clearly unacceptable. Another source gives some citations with some more specifics about the practices of Jews and Gentiles in this context:
The practical decision of the question was one of immense importance.
If it were unlawful under any circumstances to eat idol-offerings,
then the Gentile convert was condemned to a life of Levitism almost as
rigorous as that of the Jew. The distinction between clean and unclean
meats formed an insuperable barrier between Jews and Gentiles.
Wherever they lived, Jews required a butcher of their own, who had
been trained in the rules and ceremonies which enabled him to decide
and to ensure that all the meat which they ate should be clean
(tâhôr), not unclean (tamê). They could touch no meat which was not
certified as free from legal blemish or ceremonial pollution by the
affixed leaden seal on which was engraved the word “lawful” (kashar).
But Gentiles had always been accustomed to buy meat in the markets.
Now, much of this meat consisted of remnants of animals slain as
sacrifices, after the priests had had their share. So completely was
this case, that the word “to sacrifice” had come to mean “to kill” in
Theophrastus, in his ‘Moral Sketches,’ defines the
close-handed man as one who, at his daughter’s wedding feast, sells
all the victims offered except the sacred parts; and the shameless
person as one who, after offering a sacrifice, salts the victim for
future use, and goes out to dine with some one else. The market was
therefore stocked with meat which had been connected with
idol-sacrifices. The Christian could never be sure about any meat
which he bought if he held it wrong to partake of these offerings.
Further than this, he would—especially if he were poor—feel it a great
privation to be entirely out off from the public feasts (sussitia),
which perhaps were often his only chance of eating meat at all; and
also to be forbidden to take a social meal with any of his Gentile
neighbours or relatives. The question was therefore a “burning” one.
It involved much of the comfort and brightness of ancient social life
(Thueydides, ii. 38; Aristotle, ‘Eth.,’ vii. 9, § 5; Cicero, ‘Off.,’
ii. 16; Livy, viii. 32, etc.).
It will be seen that St. Paul treats it
with consummate wisdom and tenderness. His liberality of thought shows
itself in this—that he sides with those who took the strong, the
broad, the common-sense view, that sin is not a mechanical matter, and
that sin is not committed where no sin is intended. He neither adopts
the ascetic view nor does he taunt the inquirers with the fact that
the whole weight of their personal desires and interests would lead
them to decide the question in their own favour. On the other hand, he
has too deep a sympathy with the weak to permit their scruples to be
overruled with a violence which would wound their consciences. While
he accepts the right principle of Christian freedom, he carefully
guards against its abuse. It might have been supposed that, as a Jew,
and one who had been trained as a “Pharisee of Pharisees,” St. Paul
would have sided with those who forbade any participation in
idol-offerings. Jewish rabbis referred to passages like Exod. 34:15;
Numb. 25:2; Ps. 106:28; Dan. 1:8; Tobit 1:10, 11. Rabbi Ishmael, in
‘Avoda Zara,’ said that a Jew might not even go to a Gentile funeral,
even if he took with him his own meat and his own servants. The law of
the drink offering forbids a Jew to drink of a cask if any one has
even touched a goblet drawn from it with the presumed intention of
offering a little to the gods. Besides this, the Synod of Jerusalem
had mentioned the eating of idol-offerings as one of the four things
which they forbade to Gentile converts, who were only bound by the
Noachian precepts (Acts 15:29). But St. Paul judged the matter
independently by his own apostolic authority. The decision of the
synod had only had a local validity and was inapplicable to such a
community as that of Corinth. St. Paul had to suffer cruel
misrepresentation and bitter persecution as the consequence of this
breadth of view (Acts 21:21–24); but that would not be likely to make
him shrink from saying the truth. This treatment of the subject
closely resembles that which he subsequently adopted in Rom. 14.2
1 Craig S. Keener, The IVP Bible Background Commentary: New Testament (Downers Grove, IL: InterVarsity Press, 1993), 1 Co 8:1–13.
2 1 Corinthians, ed. H. D. M. Spence-Jones, The Pulpit Commentary (London; New York: Funk & Wagnalls Company, 1909), 263.