For years I have taught seminary courses and led retreats and spoken at conferences that have to do with Christian Spirituality. Topics I both teach and practice include: Personal Transformation; History of Christian Spirituality; Prayer; Keeping a Spiritual Journal; Biblical Meditation; Hearing the Voice of God; Entering Into the Presence of God; and so on.
One of the authors who has influenced me is Howard Thurman. Thurman, to me, is THE African-American scholar on all things spiritual in the sense referred to above. I am now, daily, reading through Thurman's beautiful Meditations of the Heart. Waiting next to be read is Howard Thurman: Essential Writings.
Thurman was mentored by Quaker prayer-scholar Rufus Jones. Thurman's work is dead-on biblical. He reminds me a lot of Henri Nouwen and Thomas Merton. Thurman leads us to the necessary foundation for all truly authentic and relevant Jesus-following; viz., a life that consistently dwells in the presence of God.
Here's a Thurman quote to digest, slowly: "What a man is, what his plans are, what his authentic point is, where his life goes - all is available to him in the Presence. How foolish it is, how terrible, if you have not found your Island of Peace within your own soul! It means you are living without the discovery of your true home." (Meditations of the Heart, 18)