define "self". spiritual growth is a path of expanding one's identity from the individual, to the family, to the clan, to the race, to the nation, to the species, to the genus, to all life, and ultimately to consciousness itself.
service to others is an outward approach, with a wide range of spiritual and religious systems and communities to support and motivate the seeker along the way.
service to self is an inward approach that leads to the same end. service to self doesn't mean serving the sack of cells that we carry around, but culminates with serving the greater self - the universal consciousness within.