"Bless those who persecute you; bless and do not curse them. Rejoice with those who rejoice, weep with those who weep. Live in harmony with one another; do not be haughty but associate with the lowly; never be conceited. Repay no one evil for evil, but take thought of what is noble in the sight of all." (Romans 12:14-18)The characteristic that must define a Christian, and reveal his faith to others is the merciful love he practices in the manner of His Master. This love can be witnessed in many exterior deeds of selfless charity, but to truly radiate from the soul, it needs to be cultivated interiorly as well.
Sometimes it can be easier to help those in want rather than be happy for those in plenty. St. Paul's exhortation is too easily perverted when one rejoices at another's misery, and weeps at another's gain. Frequently forgotten is our kinship with our brethren through the Mystical Body of Christ, and subsequently the truth that all is in God's Providence. To envy another's good fortune is to begrudge the generosity of Our Heavenly Father, and question the wisdom of His will.
She, who bore Wisdom Incarnate, gives us the supreme example of a compassionate heart, devoid of all bitterness. Though He belonged to her for thirty years, she peacefully accepted His departure and allowed others to attend to His needs. Mary intimately knew Her Son, gladly giving her whole self to Him, but was not jealous nor selfish when she saw He would now give His whole self to the world. We can imitate her by willfully choosing generosity over jealousy, gratitude over self-pitying.
It was revealed to St. Gertrude that when she thanked God for the blessings given to another, she was given many more graces than if she had received those particular blessings herself. Let us praise God for His gifts for us and for others.