NOTES for Co1 10:23-33
The apostle's practical advice concerning food sacrificed to idols is fairly simple. If no one points out to you the fact that the food offered to you is dedicated to some pagan god or spirit, eat calmly: there is no need to be hypervigilant and calculate every possible chance of being defiled by food sacrificed to idols.
This is understandable: Paul understands perfectly well that, in essence, all the gods and spirits of the Gentiles are nothing for a Christian, because even though they may be entirely real created (and sometimes fallen) spirits, they cannot stand against the power of the Kingdom and its breath. Christians have nothing to fear from any harm caused by these spiritual beings in themselves. The problem is not in them, but in people and in witness.
All things are lawful; one may even eat food sacrificed to idols. But will such conduct become a counter-witness? In some cases it plainly will. For example, when you come to the house of a pagan (in those days, essentially, simply to the house of a secular person), and he offers you food while mentioning that what is offered has been dedicated to one of the pagan gods. By sharing such a meal, you involuntarily share your table companion's attitude toward his god as well, and here there is already an actual betrayal of Christ, and in the sight of someone who may have wanted to see in you an example of faithfulness to Him, not indifference.
In any case, such indifference certainly will not become a witness. It is another matter if the host simply offers to share a meal with him, saying nothing at all about any gods. In that case, of course, one could begin a vigorous interrogation of the host about whether the food he has offered happens in some way to be food sacrificed to idols. Perhaps he himself knows nothing of the sort, but if one thinks and remembers... in short, in such a case the meal would most likely end before it began.
And the master of the house, an ordinary secular person, would be convinced that Christians are people somehow "hung up" on religious prohibitions, people with whom it is impossible to sit at one table: they will torment everyone with their careful investigation of everything on the table for religious purity. Such a "witness" can hardly be considered Christian. This is Paul's starting point: if one's own conscience does not condemn, then one must think about how one's behavior can serve the witness to Christ and to the Kingdom, and act accordingly.