The words "poor in spirit" are an unsatisfactory translation, and do not convey the real meaning of the text. There are certain words in the original which cannot be accurately translated. In Sufi terms this poorness of spirit is called Halim Taba", and means mild-spirited. The more true meaning of the words is, "Blessed are the mild in ego", and this is the teaching of Jesus throughout. He himself is spoken of in the Bible as "the Lamb of God", conveying the meaning of the mild in ego, like a lamb.