Listen. Ask some questions. Restate the person’s answers in my own words to be sure I understand. Try to figure out what the problem–really–is.
See if they will calm down enough to really converse.
If and when the person adjusts to a more open attitude, attempt to throw light on how the words of Christ and Scripture–thoughtfully considered–apply to the kinds of questions this person is asking and the needs he/she manifests.
If the person does not calm down, try to close the conversation on as friendly a note as possible.
Determine to pray faithfully for him/her.
Get hold of new information and revelation–in my own study of the Word of God and in what others may help me with–that may increase my understanding and my ability to communicate.