* "Her heart was a warm hearth, welcoming everyone with its gentle glow." (This metaphor compares the person's kindness to a warm fireplace that invites people in.)
* "His kindness flowed like a river, nourishing everyone it touched." (This metaphor compares the person's kindness to a life-giving river that provides for others.)
* "She was a beacon of kindness, shining brightly in the darkness." (This metaphor compares the person's kindness to a lighthouse that guides people through difficult times.)
These are just a few examples, and you can come up with many more depending on the specific context and the feeling you want to convey.