The morality of the prophet is connected to a second characteristic of prophetic personhood–the prophet is a mystic. Mysticism is a necessary pre-requisite if the prophetic task is to occur.
For some, the necessity of mysticism takes getting used to because the word ‘mystic’ carries a lot of baggage–at its worst a description of someone “who is so heavenly minded they are of no earthly good.” If that is our operational definition of mysticism, it can never be used to describe prophetic personhood. Whatever else prophets were, they were people called to do much earthly good. In fact, it was their ordinary down-to-earthness that gave them added credibility.
So, this post rests upon another definition of ‘mystic’–a definition that is the historic and classical one–namely, a mystic is someone who believes that a direct experience of God is possible precisely because we are made in the image of God, a likeness that makes a relationship with God possible.  We have a God-made capacity for relationship, and our desire for it is the deepest hunger of our hearts. From that center point we live, move, have our being and engage in the tasks to which God calls us
With this understanding of mysticism, we can properly use the word ‘mystic’ to describe prophetic personhood. And from this vantage point, several important things can be seen.
First, the prophet is a God-oriented person. Eugene Peterson says it this way: “First God. God is the subject of life. God is foundational for living. If we don’t have a sense of the primacy of God, we will never get it right, get life right, get our lives right. Not God at the margins; not God as an option; not God on the weekends. God at center and circumference. God first and last; God, God, God.”  With respect to the prophetic task, this means the prophets always know that their ministry is a divine gift, not a human impulse.  That is, the prophet is one who lives vocationally–lives with a sense of call.
Second, the prophet is a love-saturated person. How could it be otherwise if we are in relationship with God, who is love (1John 4:8) and who manifests love (‘hesed’ in the Old Testament and ‘agapé’ in the New Testament) directly through the Holy Spirit and indirectly through us, as the love of God is shed abroad in our hearts (Romans 5:5) . Brueggemann notes that prophets are lovers because they are in an ongoing lover/beloved relationship. 
Third, the prophet is a compassion-driven person. In the lover/beloved relationship, compassion (i.e. love for others) is our first response. We love because God first loved us (1 John 4:19). God’s compassion is revealed in Exodus 3, as God’s having heard the cry of people, seen their oppression–and come down to deliver them. Moses, as God’s first prophet, is one who is to have eyes to see and ears to hear–and then to act to deliver God’s people.
Compassion is the sign that we have God’s heart and that we are willing to be instruments of God’s peace. In classic Christian formation, the “gift of tears” is often the sign that we have a heart of compassion. Brueggemann puts it this way, “I believe that the proper idiom for the prophet…is the language of grief.”  We see this same compassion evidenced in Jesus multiple times in the gospels, and climaxing when his prophetic heart moved him to weep over Jerusalem (Luke 19:41-44).
Taken together, these qualities create the prophet who is mystic–that is, one who embraces, embodies, and expresses the great commandments, loving God and loving others. . Far from being irrelevant, the prophets (as mystics) join together what humans (empire) have put asunder. Prophets work to restore what has fallen apart.
 Evelyn Underhill’s classic work, Mysticism, originally published in 1911 and republished many times since, has redeemed the concept for many people. Underhill’s life and work, in addition to her writing, show the down-to-earth nature of mysticism. In 1914, she wrote Practical Mysticism, making it even more clear that to be a mystic is to live fully in the world.
 Eugene Peterson, Conversations: The Message Bible With Its Translator, since retitled, The Message Study Bible (NavPress, 2007), 24.
 Brueggemann’s latest book, Gift and Task (Westminster John Knox Press, 2017) pays tribute to the connection between God’s generosity and the prophetic task; that is, the prophet is one who is invited (a sign of divine generosity) to be a co-creator with God. This same connection also appears in earlier books by Brueggemann.
 In The Prophetic Task, Second Edition, Brueggemann shows that love is the reason for the covenant and its essence, 76.
 The Prophetic Task, Second Edition, 46. After this quote, Brueggemann moves into an eleven-page exposition of the idea, using Jeremiah as the illustration of it. For more on the idea of “the gift of tears,” see a book Brueggemann himself recommends, Daniel Berrigan’s Isaiah: Spirit of Courage, Gift of Tears (Fortress, 1996). In historic.Christian spirituality, Ignatius of Loyola is one who speaks about praying for the gift of tears.