When God is argued to be, or simply described as being, omnibenevolent and all-loving, atheists sometimes respond that such a being cannot be the God of the Old Testament, because of occasions on which He has commissioned the killing of human beings.
The typical examples mentioned are when God flooded the world sparing only Noah and his family, God’s instruction to the Israelites to genocide the Canaanites, and when God “sent 2 bears to merc a bunch of kids for mocking a bald guy” (as it was put to me).
This topic is a special favourite among anti-theists, which, owing to the inherent difficulty in resolving the paradox between being all-loving and commissioning murder, has stopped many a Christian apologist in his tracks. It becomes more difficult to address still, when we include the “Thou shalt not kill” commandment in the analysis. I’ve heard many people remark on the difference in character of the God in the Old and New Testaments, and I even heard a Christian on a call-in show mention outright he “doesn’t do” the Old Testament; I suspect this is why.
There is, therefore, a considerable bounty on providing a way to resolve these apparent inconsistencies, so that Christians get the upper hand in the debate.
One way to explain the difference in God’s character between the OT and the NT would be that omnibenevolence is the property of a function by which God always strives toward a certain goal, but which can appear (if the whole system and its outcomes aren’t considered) to take non-benevolent courses of action when circumstances aren’t optimal.
This is rational: someone’s reply to us is conditional on what we have just asked them, as well as on our behavior up until now. Different replies don’t imply an inconsistency in that person’s principles. A person can hold themselves to a standard, yet still behave differently in response to different stimuli while doing so.
But why can’t God, in His omnipotence and omnibenevolence, just make life as spiritually-easy as possible for all human societies? And regarding the Genesis flood, the Canaanite slaughter and the 42 “kids” getting merc’d by 2 bears, why can’t God refrain from taking human life in all situations, in order to have an impeccable record?
Since free will exists on both sides of the Man-God relationship, each side approaches the other only with the level of trust, openness and generosity that is warranted by the way each party models the other. If we’re a bunch of promiscuous cannibals who practice human sacrifice, God might withhold a lot of investment from us. If we’re the repentance-focused subculture of an already thoroughly devout, Messiah-awaiting culture, God may indeed send a significantly valuable Messiah to us.
But can’t God, in His omnipotence, simply override by force any negative consequences that materialise from our free will? Well, human beings aren’t just physical, they are also metaphysical (this follows from free will). Being metaphysical, as well as being sentient language processors, they contribute metaphysically toward the system by which God omni-benevolently strives toward His goal. Being connected to the metaphysical system by which reality evolves in combination with possessing free will, means that human beings have the potential to undermine that system. As an error-checking mechanism then, God on His variable level acts as a channel or filter for human contributions to the metaphysical system, in a manner contingent on those contributions and their history. This way, God’s actions in relation to human beings can be understood as a consequence of what they have previously done (this context is necessary because they have free will). This means that God can feed back on humanity contingently on God's present state as well as contingently on what metaphysical contents humanity is responsible for feeding into the system. If an agent engages in patterns that feed negatively back on, and thus undermines SCSPL, then that agent is ultimately removed from the system.
The whole point of having free will is that our actions matter, both locally and globally. If God simply erased all the contributions we make that compromise the metaphysical system responsible for upholding reality’s continual improvement, then our actions wouldn’t actually matter. Similarly, if we didn’t feed metaphysically back into God's state, our relationship history with God wouldn’t matter either and furthermore would be difficult to understand. Thus, God ends up having a variable level on which “God evolves” just as humanity evolves, while the function to which His omnibenevolent characteristics owe exists on an invariant level. God’s relationship with us is subject to variation, conditional on our own state (itself a variable). God isn't just a self-preserving function, He also has His own state. Omnibenevolence must have a self-defence failsafe within the overall life-preserving system, otherwise it isn’t truly omnibenevolent! Goodness has to defend itself from its own destruction, while allowing for free will and for itself to be comprehensible to its internal participants. If the state of humanity overall remains primitive, then God in turn may seem to behave in primitive ways. But given the contingency on humanity’s contributions and current spiritual state God has subjected Himself to, His actions remain omnibenevolent insofar as they strive toward the improvement of the whole system.
So when it comes to how God presents Himself to us, and enters into agreements or covenants with us, this is dependent on our moral standing and what stage we are at in terms of how we relate to and model God. As our moral standing improves, the better we feed into God’s identity, and more of God’s goodness and truth becomes available to us. God’s love is a relationship that is subject to evolution depending on the state of telic agents and how those telic agents have contributed to God’s evolution in actuality.
This *should* make intuitive sense to us: because on an interpersonal level, we treat someone with far more trust and openness if they’ve contributed towards us positively. Exactly like the SCSPL relationship here given, such cases involve language processing (i.e., evolution of state) on both sides of the relationship.
With this addition to our model... being a sinful, ungrateful hedonist with no spiritually significant (read: locally/globally benevolent) development ahead of him means that you are in fact directly harming God. With this development, we’ve now found an additional reason why God should remove you from the system.
We can now understand why the God of the Old Testament behaved wrathfully in those situations. In the case of the Genesis flood and the Canaanite slaughter, God had identified those who were driving global utility downward and were not only not contributing, but a threat to those few who were guiding God’s evolution in a positive way. On careful interpretation of 2 Kings 2, we find that the 42 “kids” were actually male adolescent youths. Kids/boys wouldn’t have had the strongly held religious inclinations, or understood enough who the prophets were, to cause them to chase Elijah and tell him to “go up, go up, baldy”. Secondly, telling him to “go up” (to Heaven) is a threat, and they were likely surrounding him and shouting at him. So God sending those 2 bears actually makes this the same situation as the Genesis flood and the Canaanite slaughter – one of self-defence on behalf of those who have the potential to develop both humanity and God positively.
This model wherein God evolves contingently on human behavior at His variable level also appears to explain other mysterious religious phenomena. For example, why God might ignore certain people for a time, rather than appearing on command. Or, why we might struggle to enter deeper states in prayer and go through spiritual dry patches. It’s a framework for understanding that may be able to explain how certain individuals obtain for the rest of humanity, greater degrees of openness from God. The nun Marguerite-Mary Alacoque, by dedicating herself to praying for reparations for sinners, was able to obtain a new devotion to the Sacred Heart of Jesus in a series of apparitions of Jesus. Individuals who capitalize on this and demonstrate themselves to be willing to shoulder the greater responsibilities involved, by practicing the devotions, can expect to receive benefits. There is a pattern at work here: while the Prophets trailblazed ahead, emphasized repentance and earned humanity the right to a Messiah, to benefit from this comes at the price of acknowledging one’s own sin and repenting. Similarly, a nun or a monk can dedicate their entire lives to praying for reparations for sinners, but the closer covenant with God they earn for the rest of humanity comes with it greater sacrifices (e.g., an extra devotion, going to Mass on first Fridays) from those who choose to take advantage of the benefits on offer. Maybe something similar can be said of the CTMU and its author.
So to answer the question of why the God of the New Testament seems so different to that of the Old Testament, the answer is that it's because humanity has improved so much in its moral understanding and relationship with God, as a result of all those who have developed Christianity, that the way God deals with threats to His evolution on the human scale is quite different to what it was in the time of Noah and Elijah. Nothing in principle stops this relationship from backsliding, however.