This is an interesting thread with many good observations from Darren, Dwight, Kat, M.G. and all who posted. I am just going to add a few observations.
Abraham knew that Isaac was a miracle child born to a barren woman, a gift from God. Abraham saw first hand how God created Isaac's life, owned Isaac's life and that God could take it away and restore it once again. Abraham showed faith in the most extreme fashion, as a parent it is easier to imagine and accept our own death than it is our child's death. Abraham was willing to make the ultimate (parental) sacrifice because he had faith that God could and would restore it at the resurrection.
Let me ask a question from a different perspective, would we, do we want our children to die to the flesh and become spiritual creatures? When we share the Truths of His Word (take the Sword to them so to speak) and set an example of godliness are we not slaying our children to the world? Are we not doing this in the hope that they will lose their carnality and have it replaced by His Spirit?
As far as the destruction in the OT goes we must remember the spiritual message contained within these "atrocities" bringing to mind that Israel represents spiritual Israel, the elect who will be a part of the Lake of Fire burning out all the carnal nature of the unconverted souls.
We have gone round and round with this before, when we look at the OT scriptures that speak of destruction and look at them with the mind of man we are tempted to ask ourselves;
Job 4:17 Shall mortal man be more just than God? shall a man be more pure than his maker?
Unless we look at these OT examples with spiritual rather than natural eyes we lose the true meaning;
1Co 2:14 But the natural man receiveth not the things of the Spirit of God: for they are foolishness unto him: neither can he know them, because they are spiritually discerned.
Destroy or destruction seems to have been translated from many original Hebrew words, I will post some of them below;
H4229
מחה
mâchâh
maw-khaw'
A primitive root; properly to stroke or rub; by implication to erase; also to smooth (as if with oil), that is, grease or make fat; also to touch, that is, reach to: - abolish, blot out, destroy, full of marrow, put out, reach unto, X utterly, wipe (away, out).
H7843
שׁחת
shâchath
shaw-khath'
A primitive root; to decay, that is, (causatively) ruin (literally or figuratively): - batter, cast off, corrupt (-er, thing), destroy (-er, -uction), lose, mar, perish, spill, spoiler, X utterly, waste (-r).
H5595
ספה
sâphâh
saw-faw'
A primitive root; properly to scrape (literally to shave; but usually figuratively) together (that is, to accumulate or increase) or away (that is, to scatter, remove or ruin; intransitively to perish): - add, augment, consume, destroy, heap, join, perish, put.
H3772
כּרת
kârath
kaw-rath'
A primitive root; to cut (off, down or asunder); by implication to destroy or consume; specifically to covenant (that is, make an alliance or bargain, originally by cutting flesh and passing between the pieces): - be chewed, be con- [feder-] ate, covenant, cut (down, off), destroy, fail, feller, be freed, hew (down), make a league ([covenant]), X lose, perish, X utterly, X want.
H4889
משׁחית
mashchîyth
mash-kheeth'
From H7843; destructive, that is, (as noun) destruction, literally (specifically a snare) or figuratively (corruption): - corruption, (to) destroy (-ing), destruction, trap, X utterly.
H3423
ירשׁ ירשׁ
yârash yârêsh
yaw-rash', yaw-raysh'
A primitive root; to occupy (be driving out previous tenants, and possessing in their place); by implication to seize, to rob, to inherit; also to expel, to impoverish, to ruin: - cast out, consume, destroy, disinherit, dispossess, drive (-ing) out, enjoy, expel, X without fail, (give to, leave for) inherit (-ance, -or), + magistrate, be (make) poor, come to poverty, (give to, make to) possess, get (have) in (take) possession, seize upon, succeed, X utterly.
There is more there and this word deserves study keeping in mind how through the LOF process spiritual Israel will (with Christ) totally and completely eliminate all carnal thoughts, actions and deeds from every creature. Also, that God has the power and authority to give life, form the circumstances in our lives and to take life as He wills and pleases, all according to His plan of creating immortal, incorruptable Sons and Daughters.
His Peace and Wisdom to you,
Joe