If life has those moments — ecstasies of health, youth and peace... — treasure them.

The line urges an ethic of attentive gratitude: when life offers rare intervals of untroubled well-being—“ecstasies” associated with health, youth, and peace—one should consciously value and preserve them in memory and practice. The ellipsis suggests the speaker is listing exemplary conditions that are often temporary and easily taken for granted. “Treasure them” implies both emotional appreciation and a kind of stewardship: recognizing such moments as fragile, nonrenewable gifts amid life’s inevitable hardship, aging, and conflict. The quote’s force comes from its contrast between fleeting intensity (“moments”) and the deliberate act of cherishing, implying that meaning can be cultivated by noticing and honoring what is good while it lasts.