First impressions are very important and often critical before court. In this context, the first impressions are initial impressions of certain legal problems that lawyers bring in. The first impressions determine in which way cases are to be judged in the court. Lawyers are very much cautious about how to present them as they would like to show to the jury.
Medical practitioners consider that first impressions in diagnoses are not negligible. A surgery who I often see tells me that first impressions don't include any prejudice that comes out of conversations between doctors and patients. Many doctors have told me that you should listen to patients to avoid your prejudices. I asked him the reason that he has had a belief against that. He told me that he would like to know whether patients before him could tell him the truth of their symptoms. He would like to check the credibility of patients.
His story is suggestive to me and matches my experiences as a lawyer. Lawyers have a strong belief that is inherited from their mentors: "Clients never tell you their truth". Before going into the check of their statements, lawyers have to decide whether the person before them is a lire. You don't need the six sense for your judgment. Voice, eyes, hands, many body languages are easy to tell you who they are.
I happened to see a lawyer whom I had never met and just talked on line. The first impression of his voice sounded as he might hide something critical on the case between him and me. His first impression before the court looked very much masterful. However, I was always doubtful of his way of court management. After almost two years, I found him on a serious fraud on the case. In the very final process that was almost closing the case, this guy made a critical mistake that revealed his crime. My first impressions on him were Bingo without doubt.
I guess that Church never obviously agrees with me about my belief of the first impressions. However, Lord Jesus tells in His Gospel, Matthew 10:16: "I am sending you out like sheep among wolves. Therefore be as shrewd as snakes and as innocent as doves". In social life, you must be shrewd as snakes against evils and be as innocent as doves to Lord. Otherwise, you shall be stripped of all your fortune. First impressions are a treasure that God gifts you as a weapon for the battles against the evils hidden in the world.