In the Shadow, in the Light Lyrics
I'll be always on your side
In the shadow, in the light
But I'll always be aside
In the shadow, in the light
Hell is happy, heaven is sad
And that's the result of our brain
Insane
By day and by night
Every tile's a part of life
If it's shadow, or if it's light
I'll be always on your side
In the shadow, in the light

I interpret this song to be about 'facets' of your personality/soul.....You have the good/Bad the positive/negative....The loving/hateful.
"I promise you, for all my life I’ll be Always on your side In the shadow, in the light"
'You' are telling 'you' this...I think this, cause the only person that can 'accept' every part of us...right down to the 'ugliest' thought is 'ourselves'....In the 'shadow' means The darkness/Bad/Evil us......In the 'light' means the lightest/good/pure part of us.
"I’ll follow you, wherever life goes But I’ll always be aside In the shadow, in the light"
Again the good/Bad...When one is the more 'dominant'....The other is waiting in the wings for it's moment.
"But if we don’t understand… Hell is happy, heaven is sad And that’s the result of our brain… Insane…"
The times when we can twist and 'lie' about everything just to make it easier...Yes, the brain can truly be 'insane' sometimes...Whether it's mental illness or just bad times...We can make ourselves believe whatever we choose to....Yes, sometimes 'Hell' is happy...Sin can be intriguing/addictive...Yes sometimes 'Heaven' is Sad, cause you can find happiness there, but it inevitably leads to pain.
"Caravan of life By day and by night Every tile’s a part of life If it’s shadow, or if it’s light"
Again the 'facets' of you....You go on the journey hence the 'caravan of Life'....but they come too for when you're in the 'shadow' or 'light'......'Every tile's a part of life' means Life encompasses everything...The ugly and the beautiful.
"I promise you, even when the tide is high I’ll be always on your side In the shadow, in the light"
When 'the tide is high' means both the 'happiest' and the 'saddest' moments....Regardless of how happy you are your negative/bad side will always be in the distance for when it's 'needed' and vice versa for the light/good side.
Yeah...so this is what i think :D