Parents, inaction is the greatest curse that ever came upon youth. Your daughters should not be allowed to lie late in bed in the morning, sleeping away the precious hours lent them of God to be used for the best purpose, and for which they will have to give an account to God. The mother is doing her daughters great injury in bearing the burdens the daughters should share with her for their own present good and future benefit. The course many parents pursue in allowing their children to be indolent and to gratify a desire for reading romance, is unfitting them for real life. Novel and story-book reading is the greatest evil that youth can indulge in. Novel and love-story readers always fail to make good practical mothers. They live in an unreal world. They are air- castle builders, living in an imaginary world. They become sentimental, and have sick fancies. Their artificial life spoils them for anything useful. They are dwarfed in intellect, although they flatter themselves that they …
"Whatsoever thy hand findeth to do, do it with thy might; for there is no work, nor device, nor knowledge, nor wisdom, in the grave, whither thou goest."
Both passages encourage diligence and making the most of one's time and opportunities. EGW applies it specifically to youth and avoiding idleness, while Ecclesiastes speaks more generally.
"All the powers of the mind should be called into use, and developed, in order for men and women to have well-balanced minds. The world is full of one-sided men and women, because one set of the faculties is cultivated, while others are dwarfed from inaction. The education of most youth is a failure. They overstudy, while they neglect that which pertains to practical business life. Men and women become parents without considering their responsibilities, and their offspring sink lower in the scale of human deficiency than they themselves. Thus we are fast degenerating. The constant application to study, as the schools are now conducted, is unfitting youth for practical life. The human mind will have action. If it is not active in the right direction, it will be active in the wrong. And in order to preserve the balance of the mind, labor and study should be united in schools. CE 17.2"
"For the body is not one member, but many."
While 1 Corinthians 12:14 speaks of the body having many members, EGW speaks of the need to develop all faculties of the mind. Both passages address the importance of balance and not neglecting certain aspects.