Please provide 5 definitions of faith by different scholars and theologians, along with their references.

1. "Faith is the assurance of things hoped for, the conviction of things not seen." - Hebrews 11:1 (Bible)

2. "Faith is taking the first step even when you don't see the whole staircase." - Martin Luther King Jr.

3. "Faith is the substance of things hoped for, the evidence of things not seen." - St. Augustine

4. "Faith is the art of holding on to things your reason has once accepted, in spite of your changing moods." - C.S. Lewis

5. "Faith is not belief without proof, but trust without reservation." - D. Elton Trueblood

1. Karl Barth (Protestant theologian): "Faith is the knowledge of God in Jesus Christ, which is given by the Holy Spirit, and which makes the believer a new creature." (Church Dogmatics, I/1)
2. Paul Tillich (Protestant theologian): "Faith is the state of being ultimately concerned about something that transcends us." (Dynamics of Faith)
3. Alister McGrath (Anglican theologian): "Faith is a trust in the character and promises of another person." (Christian Theology: An Introduction)
4. David Bentley Hart (Orthodox theologian): "Faith is the reception of the uncreated Energies of God, whereby we are deified by participation in the divine nature." (The Experience of God)
5. Nikki Giovanni (African American poet and author): "Faith is not a noun, it's a verb. It's not a theory, it's a practice." (The Collected Poems of Nikki Giovanni, 1968-1994)