Then when, in your point of view, does a person become "subject for the need of salvation?"
The criteria in your earlier post was the ability to decide.
What gives a person the ability to decide, and thus "subject for the need of salvation?"
It is when they are of an accountable age. When we are infants and small children, we do not fully understand the consequences of our actions. We do not have the comprehension necessary to make a decision for or against Christ. Each person reaches this point at a different time.