We have said that the Bereans were commended for listening with open minds to teachings which they had never heard before. Yes, when they were confronted with them. It was the Athenians, not the Bereans, who made it their policy to consider as many viewpoints as possible on every subject (Acts 17:18-21).
The strength of the Bereans was that they kept close to the Scriptures. When confronted with some new doctrine, they did indeed give it an interested hearing, but then “searched the Scriptures daily whether those things were so” (Acts 17:11). Had they found anything in Paul’s message which contradicted the Scriptures they would immediately have rejected it. And for this God calls them “noble”. They were the truly great, the spiritual aristocracy of their day.
Too many believers today aspire to be like the Athenians rather than the Bereans. They say they wish to have open minds, and this is good if it is remembered that an open mind is like an open mouth; not everything should be put into it.
The Athenians went to the other extreme from the Thessalonians, who would not even consider a new doctrine when confronted with it — would not even consider it in the light of the Scriptures.
The Bereans were the wisest of the three. They kept close to that blessed Book, and, when confronted with unfamiliar teachings, immediately subjected them to the test of Scripture.
This is the wisest course, even if only because we are all limited in time and strength. Obviously we cannot spend a great deal of time looking into the conflicting teachings of men without sacrificing a great deal of much-needed time for Bible study, and in the measure that we do this we are bound to grow spiritually weaker. source