It is not an assumption to say that we are to imitate God in our dealing with our enemies. Jesus said it directly. No other meaning could justly be taken from the words I quoted in Matthew 5 and Luke 6. God is our role model. "Be imitators of God, as dear children" (Eph.5:1).It must be said that it is a great assumption to say that if God commands us to do something that is reflective of Him, then He must always act accordingly in all of His dealings. This is not true biblicaly.
We are not told that we should not avange ourselves because God will avenge Himself. We are told not to avenge ourselves because God will avenge us. In other words, the verse is not talking about God's policies toward His enemies, but about His policies toward our enemies. If we wish to learn of God's attitude toward His own enemies, we are told plainly enough, in Romans 5:6-10.Beloved, never avenge yourselves, but leave it to the wrath of God, for it is written, "Vengeance is mine, I will repay, says the Lord."
If I were a judge, I would be required to avenge the wrongs done against innocent victims, but, if I am a forgiving sort, I might still forego the luxury of avenging wrongs done to me personally. Christians are told to be sufficiently gracious and merciful (I might even say, sufficiently mature) to be capable of absorbing injuries without retaliating, or even wishing to do so. I have no difficulty believing that God is mature enough to do the same. Some people picture God as being even more peevish than the best of men.
I might tell my children not to fight back against bullies (even as I do not fight back against those who bully me), because I intend to redress the wrongs done to my children in my own (more mature and just) way.
Thus, I might require my children to behave toward their enemies exactly as I behave toward my enemies, and still take on myself the responsibility to personally deal with their tormentors.
The promise that God will avenge wrongs done to His people could hardly imply a threat of eternal torment, since none of my enemies has ever subjected me to eternal torment—only to temporal suffering. To repay them with eternal torment, rather than temporal suffering, in return, would not qualify as "avenging" the wrong. It would be sheer vindictiveness. God's own law places limits upon what can be called just retribution: "an eye for an eye..."
People who believe in eternal torment often make this point. "God is not required to show mercy." It make it sound as if mercy is something He grudgingly extends to a few, in order that those few might think Him to be "gracious", but that He jealously reserves His right to exclude some, which is His real preference—and don't anyone try pressure Him to put out one modicum more of mercy than He already has conceded!Also, just because God does delight in showing mercy does not means that He always will or must, that would be mercy demanded and hence not mercy.
Perhaps this is a projection of the speaker's own attitude to that of God? It makes me wonder if the person making the point is himself reluctant to show mercy to others, but will do so only when required, and thus projects upon God the same reluctance. Yet my reading of scripture convinces me that God delights in mercy. The fact that mercy is, by definition, undeserved should be its own corrective to this idea. Since no one can require God to show mercy to sinners, how can we account for the fact that God, through Jesus, has in fact extended mercy to sinners? It must be because He wanted to do so! Does this not tell us that God's desire is to show mercy to sinners?
Of course, we must make the distinction between mercy denied in this life (and possibly for some time afterward), on the one hand, and mercy denied eternally, on the other. God may deal very severely with sinners, both in this life and in the next—but for what purpose? If the sinner's retribution is to be eternal, then the severe dealings were ineffective and of no value. They are then unnecessary (since they accomplish nothing—including the interests of strict justice), and no motive, other than God's sheer vindictiveness (a trait nowhere attributed to God in scripture), can be assigned to them. If, on the other hand, sufferings in this life lead some to repentance in this life, while sufferings after this life might lead others to repentance in that life, one would see that "mercy triumphs over judgment" after all.
Only Calvinists can legitimately claim that God wishes to show mercy to some, but reserves the right not to show mercy to others, because He doesn't want all people to be saved. For those of us who are not Calvinists, and actually believe that God loves and desires to save all sinners, the question has never been "Must God show mercy?" but rather, "Must God's desire to show mercy be eternally frustrated?"
I hope no one at this forum has ever suggested that God is never severe, or that He will ignore unrepented-of sin. The question under consideration is whether God has, or does not have, sufficient ingenuity to get what He wants for all eternity—even while not neglecting His responsibility to punish our sins.The very concept of mercy presupposes a strict judgement that is rightly deserving, possibly even ET. And because scripture makes us aware the some will receive no mercy then we must bow ourselves to God's revelation of Himself, both His goodness and severity. 'It is a fearful thing to fall into the hands of the living God.'