How is love born in the soul of man?
Love is the fruit of virtue. And love in its turn gives birth to vitue. And how does this happen?
The virtuous one does not prefer money due to his love for his brother. He does not remember evil. He is not unjust. He is not slanderous. He endures everything with courage. Love comes from all these. The words of the Lord show that love is born from virtue: Because of the increase of wickedness the love of most will grow cold.  And the words of Apostle Paul show that virtue is born from love: He that loves another has fulfilled the law. 
Therefore it is required one of these two: love or virtue. Who has one of them will have the other one as well. And on the contrary: The one who does not love will do the evil. And the one who does the evil, does not love. Hence let us strive to acquire love, because it is a fortress which protects us of all evil.
The Apostle did not say simply `love`, but `pursue love`  since it is required a hard struggle to attain it. Love runs swiftly and vanishes because many things of this world destroy it. Let us search it, let us run after it to catch it before it escapes from us.
But how will be an ever lasting love? The Apostle shows us this thing as well by saying: Honor one another above yourselves.  Love is born in this way and lasts forever.
Because there is no other better way for preserving your love than giving primacy to the other one. Thus love becomes more powerful and the other one’s esteem for us becomes more profound.
Beside respect it is necessary to show interest for the affairs of our brother, because the connection between respect and interest generates a more powerful love.
It is not enough to love with our heart but there are also needed these two ones: respect and interest which are manifestations of love and in the same time its prerequisites. They are generated by love and they also generate love.
From the book Life Topics I Saint John the Chrysostom, Oropos, Attikis, 2003
 Matthew 24, 12
 Romans 13, 8
 Corinthians 14, 1
 Romans 12, 10