This section of the sermon is, as Arthur Pink points out, closely related to the previous section, the previous being seen as negative, and this current section, positive. The Lord Jesus again makes a strong contrast between what the Rabbis taught and what he teaches, but he is certainly not finding fault with the law of Moses, nor is he substituting his own spiritually based morality in place of the moral law provide to Israel under Moses.
Our response to the unrighteous is entirely governed by the Lord’s response. Since for now he has decreed that the door remains open to allow repentant sinners to return to him, we also must welcome them and though they are our enemies on account of their treatment of us, on account of the gospel we are to show them mercy, just as the Lord did. We do not know who among them has been predestined to life until the Lord shows us; we therefore love all indiscriminately in the sense that we desire all to be saved. But when the door is shut we will approve the Lord’s judgment and be one with him in condemning the wicked. Then it will be the person and their sin that are condemned.
Is there any sense in which the Old Testament did teach that enemies should be hated? Psalm 139 might be seen as supporting this: ‘Surely thou wilt slay the wicked, O God: depart from me therefore, ye bloody men. For they speak against thee wickedly, and thine enemies take thy name in vain. Do not I hate them, O LORD, that hate thee? and am not I grieved with those that rise up against thee?’ (Psalm 139:19-21). Again, Israel was taught to regard the Ammonites and the Moabites as those who were under the judgment of God, ‘An Ammonite or Moabite shall not enter into the congregation of the LORD; even to their tenth generation shall they not enter into the congregation of the LORD for ever: thou shalt not seek their peace nor their prosperity all thy days for ever’ (Deuteronomy 23:3-6). Or those words spoken prophetically by Christ: ‘Mine enemies speak evil of me, When shall he die, and his name perish? … But thou, O LORD, be merciful unto me, and raise me up, that I may requite them’ (Psalm 41:5-10)? God also tells us what he will do to his enemies, ‘If I whet my glittering sword, and mine hand take hold on judgment; I will render vengeance to mine enemies, and will reward them that hate me. I will make mine arrows drunk with blood, and my sword shall devour flesh; and that with the blood of the slain and of the captives, from the beginning of revenges upon the enemy. Rejoice, O ye nations, with his people: for he will avenge the blood of his servants, and will render vengeance to his adversaries, and will be merciful unto his land, and to his people’ (Deuteronomy 32:41-43). Do these passages teach that it was permitted or even a duty for Israel to hate their enemies? Pink resolves this by distinguishing between private and public enemies. He says, ‘It was the public enemies of Israel and of God whom David hated.’ (He also makes a distinction between hating the person and hating the sin; it is right to hate the sin but not the person.) It was because they had come under the judgment of God that they had also come to be regarded as David’s enemies. The Lord had made his judgment known and nothing could alter that. But before the Lord reveals his fixed anger against any, we must imitate his general mercy and longsuffering even towards those who oppose us. It is God’s attitude that guides us. While the Lord holds open the door of repentance and forgiveness, who are we to shut it? Christ has sent the gospel into all the world. We therefore love the world just as God has loved the world; we love it by witnessing to Christ’s mercy, and we invite everyone to come to him without exception. In general this is our stance to all people in this life, for God does not reveal to us when a person has gone beyond the pale and is excluded from the possibility of salvation, although we know that can happen (Hebrew 10:26-27). These judgment passages in the Old Testament cannot justify a general hostility to those who have harmed us. We have already been told that we are to pray for those who persecute us and it is about to be repeated. This was also the attitude taught by the law: ‘If thou meet thine enemy's ox or his ass going astray, thou shalt surely bring it back to him again. If thou see the ass of him that hateth thee lying under his burden, and wouldest forbear to help him, thou shalt surely help with him’ (Exodus 23:4-5). On the Day of Judgment God’s verdict on all men and women will be revealed and every believer will agree with that verdict. Then, we too will be called to hate the intransigent enemies of God just as he does. But before judgment, comes mercy, and at this time we follow our Lord who said, ‘And if any man hear my words, and believe not, I judge him not: for I came not to judge the world, but to save the world’ (John 12:47).