Perfection Is Found Both According to Love of God and Love of Our Neighbor
[Since to be alive spiritually means to love, Thomas concluded that to be perfect in the spiritual life means to be perfect in love. Here he continues to examine what kind(s) of love that is.]
Having considered that perfection consists primarily in regard to charity, it is clear in what the perfection of the spiritual life consists. For there are two precepts of charity, one pertaining to the love of God, the other to the love of neighbor. These two precepts have a certain order to each other, according to the order of charity. For what we should primarily love out of charity is the supreme good that makes us happy, namely God, while secondarily we should love our neighbor out of charity, with whom we are joined in a certain social bond, in the participation of happiness; hence we should love in our neighbor out of charity in reference to a mutual attainment of beatitude. [Thomas explains (1) that we should love God in the first place, and our neighbor in relation to God, and (2) why this is so, namely because God is the ultimate locus of union with our neighbor; by Christian love we love our neighbor in God and for God, and thus we love God primarily.] And the Lord showed this order of the precepts of charity in Mat 22:37-39, saying, "You shall love the Lord your God with all your heart, and with all your soul, and with all your mind. This is the great and first commandment. And a second is like it, You shall love your neighbor as yourself." [Thomas follows the analytical explanation of the primacy of love of God before love of neighbor with a reference to the definitive, revealed foundation of this doctrine.] Therefore the perfection of the spiritual life consists first and principally in the love of God; [Divine, spiritual love is first of all love of God; therefore perfection in spiritual life principally means perfection in love of God.] hence the Lord, speaking to Abraham, says, "I am God Almighty; walk before me, and be perfect" (Gen 17:1). We walk before God not by bodily steps, but by spiritual affections. [Again, he follows the analytical argument with a scriptural basis and illustration of the doctrine.] But secondarily the perfection of the spiritual life consists in the love of neighbor; hence the Lord, having said "Love your enemies," (Mat 5:44), and having added a number of other precepts pertaining to the love of neighbor, concluded by saying, "Be therefore perfect, as your heavenly Father is perfect" (Mat 5:48).
[Divine love, and therefore spiritual life, consists primarily in love of God, and secondarily in love of neighbor. This does not mean, however, that one could seek exclusively love of God, to the neglect of love of neighbor. First, because the love of charity is the love of friendship. To love God implies loving and willing what God loves and wills. This love of God is revealed to us in Christ, who came not to be served but to serve, to give his life for us. "We love, because he first loved us." So genuine love of God as a friend necessarily flows into love of neighbor. Secondly, because we are temporal, physical beings, who are related to other human beings, and if our love does not at all express itself in the temporal, physical order towards other human beings, it can scarcely be a genuine love. As St. John puts it, "he who does not love his brother whom he has seen, cannot love God whom he has not seen."]