The Biblical references you cite here, except to a small degree Deut 1:39, don't fit ANY support of a so-called arbitrary "age of accountability."
Isaiah 7 is in reference to a "defense" -- a refusal to do evil.
Any age you provide as an "age of accountability" beyond the references you gave are of "no account":
Deut 1:39 references "little ones" who have yet to gain "knowledge between good and evil" ... and of the many toddlers & kindergarteners & early primary-age kids I've been around, I can GUARANTEE you these kids know quite a bit about "knowledge between good and evil."
Really the diatribes against infant baptism are really a slight misnomer...because they also become unbiblically justified diatribes vs. toddler baptism, kindergartener baptism, early primary age baptism as well!
Which presupposes he understands what is evil based upon moral ground.
Deut 1:39 references "little ones" who have yet to gain "knowledge between good and evil" ... and of the many toddlers & kindergarteners & early primary-age kids I've been around, I can GUARANTEE you these kids know quite a bit about "knowledge between good and evil.
Fine then, but which does not equate to a 8 day old infant or such.