grows 'with our growth'

As Man, perhaps, the moment of his breath,
Receives the lurking principle of death;
The young disease, that must subdue at length,
Grows with his growth, and strengthens with his strength:
So, cast and mingled with his very frame,
The Mind's disease, its ruling Passion came;
Each vital humour which should feed the whole,
Soon flows to this, in body and in soul.