What are the conditions for an interpreter of dreams, and how do we distinguish between an interpreter and a charlatan?

Dreams should only be interpreted by those who possess knowledge of them, for informing without knowledge is a falsehood, as Allah Almighty says: "And do not pursue that of which you have no knowledge." It is permissible to interpret them for those who know the principles of interpretation from the Quran, Sunnah (definition), Arabic language, their poetry, and proverbs, provided that they also possess virtue, righteousness, and insight. It is not permissible to interpret them merely by looking at books of interpretation, as they vary according to individuals, circumstances, times, and the descriptions of the dreamers.