Clipped

It's doubtful that Blake had much experience as a father, but he had serious misgivings about "the Heavenly Father:

See the picture.

Aged Ignorance! what might that be:

Jehovah, who came with a thump on the head!

Father, who whips (stunts) the growing sprout, for
whatever reason, basically for not obeying a convention,

School! which systematically molds (or tries to mold) the pupil into obedience.

Blake (so far as we know) was never a biological father; perhaps he understood that no (or at least few) adequately raise a son without (at least some) clipping.

The clipped son becomes a father; he may swear he'll
never do to his sons what his father did to him; but he
does.

And so it goes: inadequate fathers, inadequate schools, inadequate conventions, inadequate lives for the multitude--raised without creativity.

The dutiful multitude are the Redeemed; the rulers:
schoolmasters, judges, senators, are the Elect. A few
who escaped the clipping (or at least were clipped less) may hear the call to prophesy. They are the Reprobate:

From Milton: plate 7:
"The Elect from before the foundation of the World:
The second, The Redeem'd. The Third. The Reprobate & Form'd
To destruction from the mothers womb: follow with me my plow.
Of the first class was Satan: with incomparable mildness;
His primitive tyrannical attempts on Los: with most endearing love
He soft intreated Los to give to him......"

Aged Ignorance is really a very searching critique of society. We all could do better. Urizen was terrified of futurity. Thank God for the Saviour who brought to us forgiveness.

Read again the Intro to the chapter in Jerusalem To the Christians: Plate 77 (E231)

"We are told to abstain from fleshly desires that we may lose no
time from the Work of the Lord.  Every moment lost, is a moment
that cannot be redeemed every pleasure that intermingles with
the duty of our station is a folly unredeemable & is planted
like the seed of a wild flower among our wheat. All the
tortures of repentance. are tortures of self-reproach on account
of our leaving the Divine Harvest to the Enemy, the struggles of
intanglement with incoherent roots.  I know of no other
Christianity and of no other Gospel than the liberty both of
body & mind to exercise the Divine Arts of Imagination.
Imagination the real & eternal World of which this Vegetable
Universe is but a faint shadow & in which we shall live in our
Eternal or Imaginative Bodies, when these Vegetable Mortal
Bodies are no more."