I call it a poem because the repetition of Blessed and the stringent parallel structure of the lines—Blessed be…for…”—make it sound poetic. It also seems to be spoken forth as one would a poem. Before delivering “The States of Blessedness” to the crowds surrounding him, Jesus first climbs a mountain, presumably for better acoustics. Then—in the original Greek as in most early and some contemporary translations—Matthew goes out of his way to draw attention to the speaking itself with reference to Jesus’ mouth as well as three verbal communication verbs: “And he opened his mouth, and taught them, saying…” (Matthew 5:2 KJV).
The Beatitudes are a formal proclamation of exactly what Jesus, reading from the scroll of Isaiah in the synagogue, has already said is the reason God sent him to us in the first place: to preach the good news to the poor and miserable. “The Spirit of the Lord is upon me,” he told them, and is promising them now, “to preach the gospel to the poor; he hath sent me to heal the brokenhearted, to preach deliverance to the captives, and recovering of sight to the blind, to set at liberty them that are bruised” (Luke 4:18). These poor sufferers are the very ones surrounding him, who’ve heard of his miraculous healings and come after him with their own griefs.
And into this suffering and longing, Jesus preaches the good news.
I love Matthew's reference to Jesus’ mouth. He didn’t just teach or speak, that day on the mountainside. He opened his mouth and delivered forth blessing upon blessing, word upon word.