But the unbelieving Jews stirred up the Gentiles and poisoned their minds against the brothers (Paul and Barnabas).
Many a person has been imprisoned (or executed) for poisoning someone they planned to murder. It is a terrible crime deliberately to poison someone to death. It is also a terrible thing to poison people's minds. There are fanatical people who try to brainwash the young into believing extreme ideologies or political views or even wrong religious theories.
When Paul and Barnabas arrived at the city of Iconium, which was 80 miles from their last port of call, they began to preach the Gospel. At first things went well and many believed. But, as so often happened, unbelieving Jewish people became angry with Paul and Barnabas and the message they preached. In their anger they twisted the truth that the brothers had been preaching and "poisoned the minds" of the people against the Gospel message.
In our own day there are certain writers who deliberately set out to contradict the teaching of the Bible and to undermine and destroy the faith of people who believe in the Lord Jesus Christ. This is a 'criminal' thing to do. The poison of unbelief can be very strong, even deadly, if it turns people away from Christ. But God has a day when such poisoners will have to answer to him personally for what they have done. But God also has the word of his grace to help those whose belief is challenged to keep on believing in Jesus. His truth will triumph.
Dear Lord Jesus, I pray that you will help me to keep believing in your Word. Amen.