The God described in the Old Testament can be violent and vindictive and seems to hold to a different set of moral rules than the God we see in the New Testament. How does the Catholic church explain these differences?
A few of the better known examples of the more violent nature of the Old Testament's God are:
God asks Abraham to sacrifice his son (Genesis 22:2)
2 And he said, Take now thy son, thine only son Isaac, whom thou lovest, and get thee into the land of Moriah; and offer him there for a burnt offering upon one of the mountains which I will tell thee of.
This is then revealed to have been a "test" of Abraham's faith (Genesis 22:12)
12 And he said, Lay not thine hand upon the lad, neither do thou any thing unto him: for now I know that thou fearest God, seeing thou hast not withheld thy son, thine only son from me.
Since, by definition, the God of the Judeo-Christian faith is omniscient, this is not a test that could have provided Him with new information. It seems like a particularly horrible thing to do to a father. It is also at odds with the loving God of the later Christian faith.
The story of Lot (Genesis 19). Two angels have visited Lot's house and he treats them as honored guests. The men of Sodom ask him to let them "know" them:
5 And they called unto Lot, and said unto him, Where are the men which came in to thee this night? bring them out unto us, that we may know them.
Lot wants to protect his guests and so, instead, offers up his virgin daughters:
8 Behold now, I have two daughters which have not known man; let me, I pray you, bring them out unto you, and do ye to them as is good in your eyes: only unto these men do nothing; for therefore came they under the shadow of my roof.
This is treated as a perfectly natural offer. Any father who would offer up his daughters for rape today would be considered the lowest of degenerate criminals, yet Lot is portrayed as the only righteous man in Sodom and the only one, along with his family, who is spared by God.
The story of Lot also has two other examples of the extreme violence that the Old Testament God was capable of. The very smiting of the, presumably, hundreds or even thousands of inhabitants of Sodom and Gomorrah, and the turning of Lot's wife into a pillar of salt for the rather innocuous sin of looking back at her home while it was being destroyed:
24 Then the Lord rained upon Sodom and upon Gomorrah brimstone and fire from the Lord out of heaven;
25 And he overthrew those cities, and all the plain, and all the inhabitants of the cities, and that which grew upon the ground.
26 But his wife looked back from behind him, and she became a pillar of salt.
24 Then the Lord rained upon Sodom and upon Gomorrah brimstone and fire from the Lord out of heaven;
25 And he overthrew those cities, and all the plain, and all the inhabitants of the cities, and that which grew upon the ground.
28 And he looked toward Sodom and Gomorrah, and toward all the land of the plain, and beheld, and, lo, the smoke of the country went up as the smoke of a furnace.
As a final example, the scourges of the Pharaoh. Each and every one of them is an action that does not square with the forgiving, loving and fundamentally good nature of the Christian God, but the following is particularly cruel (Exodus: 11):
5 And all the firstborn in the land of Egypt shall die, from the first born of Pharaoh that sitteth upon his throne, even unto the firstborn of the maidservant that is behind the mill; and all the firstborn of beasts.
This is a kind and loving God who will kill innocent babies. What's more, His wrath is not restricted to the children of those, like the Pharaoh, who oppressed his people but extends to ay and all Egyptians and even goes so far as to include their animals. Clearly, a sheepherder living out in the middle of nowhere who has never seen any of the Jews living in Egypt cannot be blamed for their oppression under the Pharaoh. Yet, even this innocent shepherd is not spared God's wrath.
Now, I imagine that all of these examples has been extensively debated and there will be various interpretations and apologetics for each. My question, however, is whether Catholics believe that the nature of God has changed between the Old and New testaments. Jehova seems to be a very different God from the one described in the New Testament, how is that dealt with in the Catholic faith?
PS. I have restricted the question to the Catholic church so it is not too broad bu welcome answers that also mention the positions of other denominations.