I recently put together an annotated bibliography on kenotic theology for a course I did with the deacons of the Diocese of British Columbia, and I thought I would share it. These are books and article I used in my dissertation, Unsettling Theology.

Kenotic theology is about the self-emptying of God; as we are made in the image of God, human beings who are like this become ever more like the divine. Initially it was only about the Incarnation, drawing on the so-called Philippian Hymn in Philippians 2.5-11:

⁵ Let the same mind be in you that was in Christ Jesus,

⁶ who, though he was in the form of God,
    did not regard equality with God
    as something to be exploited,
⁷ but emptied himself,
    taking the form of a slave,
    being born in human likeness.
And being found in human form,
⁸     he humbled himself
    and became obedient to the point of death—
    even death on a cross.

⁹ Therefore God also highly exalted him
    and gave him the name
    that is above every name,
¹⁰ so that at the name of Jesus
    every knee should bend,
    in heaven and on earth and under the earth,
¹¹ and every tongue should confess
    that Jesus Christ is Lord,
    to the glory of God the Father.

It is also exemplified in passages such as Mark 10:42-45:

⁴² So Jesus called them and said to them, “You know that among the Gentiles those whom they recognize as their rulers lord it over them, and their great ones are tyrants over them. ⁴³ But it is not so among you; but whoever wishes to become great among you must be your servant, ⁴⁴ and whoever wishes to be first among you must be slave of all. ⁴⁵ For the Son of Man came not to be served but to serve, and to give his life a ransom for many.”

If you want to explore kenotic theology, I recommend:

• Law, David R., Kierkegaard’s Kenotic Christology (Oxford UK: Oxford University Press, 2013). Most of this book is about Kierkegaard, and unless you have a PhD in his philosophy you won’t be interested in the whole thing – but Law’s description of kenotic theology in the opening chapters is as good an introduction as you will find. 
• Brown, David, Divine Humanity: Kenosis and the Construction of a Christian Theology (Waco TX: Baylor University Press, 2011). This is a great history of the development of kenotic theology in the 19th century and early 20th century. 
• Polkinghorne, John, editor, The Work of Love: Creation as Kenosis (Grand Rapids MI: Eerdmans Publishing Co, 2001). This collection of essays gives you an idea of where the discussion was about twenty years ago.
• Wright, N. T., “ἁρπαγμὸς and the Meaning of Philippians 2: 5-11”, Journal of Theological Studies, NS, Vol. 37, Pt. 2, October 1986, pp. 321-352. Tom Wright can be a brilliant New Testament scholar, and this is one of his crucial essays that gets deep into the meaning of one word in Philippians 2.5-11, the key text of kenotic theology. 
• Evans, C. Stephen, editor, Exploring Kenotic Christology: The Self-Emptying of God (Oxford UK: Oxford University Press & Vancouver BC: Regent College Publishing, 2006). Arguably this is a better set of essays than in Polkinghorne’s book, and offers a better survey. 
• Bulgakov, Segius The Lamb of God (originally published as Агнец Божий in 1933), translated by Boris Jakem (Grand Rapids MI: William B. Eerdmans Publishing Company, 2008). Bulgakov picked up where the early 20th century kenoticists left off, and framed kenotic theology in terms that are acceptable in Orthodox theology. It is a long book but a rewarding one to read. The key idea is that the self-emptying of God by the Second Person in the Incarnation is, in fact, a charactersitic shared by all three persons of the Trinity, and is manifested in all their relations with Creation. 
• Fairweather, Eugene R., “Appended Note: ‘The “Kenotic” Christology’” in F. W. Beare, A Commentary on The Epistle to the Philippians (London UK: Adam and Charles Black, 1959), pp. 159-174. This is an ancient piece by one of my old professors, and Fairweather criticizes the state of kenotic theology as it had stood, more or less moribund since 1925. He had obviously not read Bulgakov, as he was pretty much unknown in the English speaking world until Rowan Williams translated some of his writings in 1999.
• von Balthasar, Hans Urs, Mysterium Paschale: The Mystery of Easter translated by Aidan Nichols (San Francisco CA: Ignatius Press, 1990). Balthasar was a major theologian of the 20th century, and in this very readable book he reflects on the Triduum and kenosis. Notably, he reflects on the “descent to hell” in kenotic terms. The book draws on Bulgakov but casts it in a modern Catholic theology. Really useful for preaching in Holy Week.
• ——————, Theo-Drama, Theological Dramatic History: Volume IV: The Action, translated by Graham Harrison (San Francisco CA: Ignatius Press, 1994).If you liked Mysterium Paschale you may want to read Balthasar’s later reflections in this text, part of his massive seventeen-volume systematic theology he wrote between 1961 and 1987 (I think he was trying to be the Catholic Karl Barth). 
• Coakley, Sarah, “Kenōsis and Subversion: On the Repression of “Vulnerability” in Christian Feminist Writing” in Powers and Submissions: Spirituality, Philosophy, and Gender (Oxford UK: Blackwell Publishers Ltd, 2002), pp. 3-39. Sarah Coakley wrote three articles on kenosis from her analytical theological and feminist perspective, and this is the first, in which she discerns issues in late 20th century kenotic theology and argues for contemplative, wordless prayer as a way to subvert patriarchy. Coakley is never an easy read, just to warn you.
• ——————, “Kenosis: Theological Meanings and Gender Connotations” in  The Work of Love: Creation as Kenosis ed. by John Polkinghorne (Grand Rapids MI: Eerdmans Publishing Co, 2001), pp. 192-210. This is her second article, where she criticises certain male authors in the same volume for unconscious gender-stereotyping in kenotic theology. 
  ——————, “Does Kenosis Rest on a Mistake? Three Kenotic Models in Patristic Exegesis” in Exploring Kenotic Christology: The Self-Emptying of God edited by C. Stephen Evan (Oxford UK: Oxford University Press & Vancouver BC: Regent College Publishing, 2006), pp. 246-264. Coakley burrows into patristic theology (particularly the Cappadociatin fathers) to argue that recent scholars have misunderstood basic aspects of kenotic theology.  
• Kilby, Karen,  “The Seductions of Kenosis”, https://www.youtube.com/watch?v=tUSujhwdMVQ, accessed January 3, 2019. Kilby is suspicious of the way in which kenotic theology can be used to valourize suffering, and in this lecture she expresses her reservations.
• McFague, Sallie, Blessed are the Consumers: Climate Change and the Practice of Restraint (Minneapolis MN: Fortress Press, 2013). The late Sallie McFague published this, and I think it may be her last work. In it she considers the writings and lives of three “saints”, namely: John Woolman (1720-1772), a Pennsylvania Quaker; Dorothy Day (1897-1980), a lay Catholic social worker; and Simone Weil (1909-1943). What is important for McFague is that each of these people not only espoused kenotic ideals, but they lived them, too, and did so in engagement with the world. Woolman advocated for abolition, Day for workers’ rights and the needs of the poor; and Weil also for workers, Spanish Republicans, and victims of the Nazi occupation of France. Each of them were outsiders.
• Carroll, Anthony J., Marthe Kerkwijk, Michael Kirwan, and James Sweeney, editors, Towards a Kenotic Vision of Authority in the Catholic Church, edited by (as Western Philosophical Studies, VIII Christian Philosophical Studies, VIII) (Washington DC: The Council for Research in Values and Philosophy, 2015). These are a fascinating set of papers from a conference held at Heythrop College, University of London.
• Martin, Ralph P. & Brian J. Dodd, eds., Where Christology Began: Essays on Philippians 2 (Louisville KY: Westminster John Knox Press, 1998). A collection of essays on Philippians 2, now getting a bit dated.
• Moltmann, Jürgen, The Crucified God The Cross of Christ as the Foundation and Criticism of Christian Theology translated by R. A. Wilson and John Bowden (London UK: SCM Press, 1974). This is considered a classic in kenotic theology by many. Moltmann follows in the tradition of the Christian left-Hegelians, and so allows for the idea that God is changed by interaction with humanity, a thesis which is unacceptable to many who wish to adhere to more traditional Christology and Trinitarian theologies, although it may appeal to folks interested in Process Theology. I was warned off of Moltmann by my dissertation supervisor (!).