Jesus made that statement to the Jews in the treasury. They were claiming to be children of God because they have Abraham as their father.
Jesus tells the Jews, their works prove who their father is. They sought to kill Jesus. This proved the devil was their father.
The same is true today. Your works prove whose child you are. What do your works say about you? Do your works prove you are a child of God?
Too many today are like those to whom Jesus was speaking. They want to make a profession they are the child of God, but their works deny that claim. Do not allow your works to discredit your profession. Let your works prove you are a child of God. Leave no doubt whose child you are.