Dante suddenly realized how prone to destruction his son had become, and through that realization, he also began to understand how hard Damien's life must've been.
People with his tendencies would never live easily. They would always challenge themselves to the extreme for the sake of results, even if they had to suffer immensely to see progress.
And, while they caused immense destruction with their own power, they would face destruction of the same level.
This was the duality of such a law.
It was the complete opposite of the gentle and patient Creation. It was wild, unruly, and unwilling to wait for anyone impeding its path.
'But it must've been such a mentality that propelled him to reach this place.'
It couldn't be mentioned enough times.
Dante's shock was incomprehensible to normal people.