The practice of compassion begins at home. We have our parents, our children, and our brothers and sisters, who perhaps irritate us the most, and we begin our practice of loving-kindness and compassion with them. Then gradually we extend our compassion out into our greater community, our country, neighbouring countries, the world, and finally to all sentient beings equally without exception.
Extending compassion in this way makes it evident that it is not very easy to instantly have compassion for "all sentient beings." Theoretically it may be comfortable to have compassion for "all sentient beings," but through our practice we realize that "all sentient beings" is a collection of individuals. When we actually try to generate compassion for each and every individual, it becomes much more challenging. But if we cannot work with one individual, then how can we work with all sentient beings? Therefore it is important for us to reflect more practically, to work with compassion for individuals and then extend that compassion further.
--from Trainings in Compassion by Dilgo Khyentse Rinpoche translated by the Padmakara Translation Group, published by Snow Lion Publications