Lambent is an adjective that means flickering with a soft radiance. 

Our word of the day comes directly from the Latin word for ‘licking,’ which was used to describe the flickering of flames. Lambent has been with us since the mid-17th century. 

Here’s an example:

The lambent of our fireplace still looms large in my childhood memories. Those soft, flickering images made me warm on the inside and out.