Katy Perry's 'By The Grace Of God' Single Debuts Off Of 'Prism' At iTunes Festival

Katy Perry hit London this week for a performance at the star-studded iTunes Festival. With just weeks until the release of her next album, "Prism," Perry used the show to debut a new track off of the record.

Perry, who also played hits such as "Teenage Dream" and "Firework," premiered "By the Grace of God." The emotional song took Perry to a vulnerable place as she sang about hitting bottom after her divorce from former husband Russell Brand.

She recently opened up to Billboard about "By the Grace of God," telling the publication, "That song is evident of how tough it really was at a certain point. I asked myself, 'Do I want to endure? Should I continue living?'" Take a listen to the new song above.

The 28-year-old singer also recently released the full tracklist to her "Prism" album, which is set to hit stores on Oct. 22. Check out the songs included on the standard and deluxe editions below.

1. Roar
2. Legendary Lovers
3. Birthday
4. Walking On Air
5. Unconditionally
6. Dark Horse
7. This Is How We Do
8. International Smile
9. Ghost
10. Love Me
11. This Moment
12. Double Rainbow
13. By the Grace of God
Deluxe edition bonus tracks:
14. Spiritual
15. It Takes Two
16. Choose Your Battles

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