Check it out yourself...
While you listen to someone, you do listen to what the person says as well to how the person speaks. Impressed by body-language, tone and pitch of voice, the quality of articulation and the way you are spoken to (you feel invited or uninvited, left-out or welcome...), you pass judgment within the first seven seconds on liking or disliking the speaker.
This first (emotional!) impression makes you decide – unconsciously – if and how far you trust the message of this person.
In this context the studies of Albert Mehrabian, (Professor of Psychology, UCLA), published in the 'British Journal of Psychology' (1971), are very interesting. He comes to the conclusion, that the non-verbal elements of communication are particularly important for communicating feelings and attitudes, specially when they are not consistent with the verbal part of the message. If words and body language disagree, one tends to believe the body language.