So Romans 3 doesn't explain the crucifixion of Jesus as being necessary for all of mankind, Jews and Gentiles alike, because sin encompasses every part of human existence and nothing else can save humanity but the atonement of Christ?
ING - Why would that verse matter to this conversation? It does not say anyone is born with sin. It says me all have the capacity, and nature to sin to some degree.
And Psalms isn't making the point in both passages that, from the very beginning, regardless of class or rank or upbringing, that everyone, including David, walks away from the path of righteousness from the moment of birth?
ING - No - they are not! Even 58:3 says after, meaning at some point after birth. And you seem to be ignoring the other words in the sentence.
Did you notice it says THE WICKED are...? Thus the Good aren't! Which plays to the side of no-one being born with sin.
Are there, then, passages, describing that there is such a thing as an age of accountability?
Is there more than one kinda-sorta reference?
ING - This comes from the Jews - 12 or 13 is the age for the ceremony to join the adults, and be accountable.
Deuteronomy 1:39 And as for your little ones, who you said would become a prey, and your children, who today have no knowledge of good or evil, they shall go in there. And to them I will give it, and they shall possess it.
Matthew 19:14 But Jesus said, “Let the little children come to me and do not hinder them, for to such belongs the kingdom of heaven.”
Ezekiel 18:20 The soul who sins shall die. The son shall not suffer for the iniquity of the father, nor the father suffer for the iniquity of the son. The righteousness of the righteous shall be upon himself, and the wickedness of the wicked shall be upon himself.
Luke 2:42-46 And when he was twelve years old, they went up according to custom. And when the feast was ended, as they were returning, the boy Jesus stayed behind in Jerusalem.
Does the age of accountability include or exclude the disabled?
ING - If you have studied this - then you know it depends on mental age if disabled.
What of the still-borns?
ING - According to the Bible and other Hebrew texts, - a fetus is just material, until the first breath of life, so obviously no accountability.
Does anything specifically state that souls, for example, don't enter the body until the brain is able to be somewhat self-aware?