Now, think about this: as we all know, our rather fragile human bodies will one day die. This event can happen when (1) our God-given purpose for living here on Earth is accomplished in His sight (2) we may die of a fatal illness (3) or we are accidentally killed during a war or some other unpredictable accident.
One day our bodies die and return to dust and, of course, we have no idea when that time will come for us as individuals, but that is when the lights of our eternal spirits will continue to live on and never, ever die.
The idea here is that our spirits are lights that will shine forever. That is why we say this God-given light of ours is eternal. In addition, our personal, individual light can never be extinguished. Keep in your mind: this light of our spirits is intended to grow brighter as we live and learn each day as humans.
It is our God directed purpose during this human experience of ours to fill our lives to overflowing with as much: love, knowledge, compassion and understanding as we can with the result that our individual soul-light will constantly grow in intensity during each of our acts of kindness toward others.
In short, this happens as we interact in a caring manor with the people around us. When we help them the light in both our lives and theirs can grow and shine much brighter. This happens because people who receive from us will just naturally, follow our example by doing the same as we did for them to the people who are a part of their lives. Therefore, the brighter our soul-light grows the closer we will, eventually, get to our goal of merging our light with God's light and thus achieve a closer "oneness" with God.
"In what way," you may ask," can what you say about "eternal soul-light" be possible?" Let me give you an "earthly" example:
Now, compare our lives to that of a mature Oak tree. Notice the branches, and the leaves (maybe thousands of leaves on one Oak tree). We could say the lights of our lives are similar to just one of those leaves. Leaves sprout in the springtime, and then with nourishment from the branches of the tree, they grow to maturity. Later in the season, the leaves change color and eventually fall off of the tree and physically "die" in the earth where they turn to dust.
But then during the next springtime, amazing as it may seem, new leaves grow on the tree and the life that seemed to us to be dead - goes on. "All things are possible with God.."(1 Cor. 6:12)
Finally, we can say in our daily prayers of thanks to God: "I want to be in the Light as You are in the Light!"