They replaced the love that is based on God’s love for us, the kind of love that comes through faith only, with a natural love – as the Lord points out, ‘Do not even pagans do that?’ So the new commandment to love our enemy is not new in a sense that it was not present in the Old Testament, rather it cuts through our sin of narrowing the circle of who our neighbor is, and brings us back to the basis of our love for neighbor and expands its scope – be perfect as your heavenly Father is perfect (48) who sends rain on the righteous and the unrighteous (45). In the Parable of the Good Samaritan in Luke 10, we see the same thing. The expert in the law knows the commandment, but asks self-righteously, ‘And who is my neighbor’ (29). And Jesus gives an amazing answer – he turns our focus from self to others, ‘Which of these… was a neighbor TO the man’ (36).
The natural love is limited and seeks its own benefit, loving those who can love us back, but the love of God which we are called to resemble is not based on who the others are and how they treat us, it is anchored in the unconditional love of our Father in heaven, it always flows out and seeks an object. The love of God is both the reason and the source of our ability to love our enemy. We love in the way he loved us first, because he loved us first; God’s love was shown to us in Christ dying for us while we were sinners (Romans 5:8), and thus reconciling us unto himself while we were his enemies (Romans 5:10). So let us obey this commandment not as those who want to show ourselves as good and righteous in front of God, but to show ourselves as the children of Father who loved us unconditionally. Let us pray to God to fill us with his Spirit, so that we can love as he loves, being true children resembling the character of their Father (Matthew 5:44-45).