# This has been offered in sacrifice

Here being offered in sacrifice means that it was offered to idols. This was the part of the meat that the worshiper was allowed to bring home after killing an animal as a sacrifice to an idol.

# for the sake of the one who informed you

This is the first reason not to eat the meat. Alternate translation: "for the good of the one who informed you"

# and for the sake of conscience

This is the second reason not to eat the meat. Alternate translation: "and because of conscience" or "and in order not to cause concerns about whether or not it is sinful"