Who does not grow, declines.

This saying is attributed to Hillel the Elder (late 1st century BCE–early 1st century CE), a leading Jewish sage associated with the formative period of rabbinic Judaism. It reflects the ethical and pedagogical culture of the early rabbis, in which continual study (Torah learning), refinement of character, and growth in wisdom were treated as lifelong obligations rather than achievements one could “finish.” Many of Hillel’s maxims are preserved in rabbinic literature, especially in Pirkei Avot (Ethics of the Fathers), a tractate devoted to concise teachings about learning, humility, and moral conduct. The sentiment fits that milieu: spiritual and intellectual life is dynamic, and stagnation is understood as a form of regression.

The aphorism frames human development as a choice between ongoing growth and inevitable decline. It rejects the idea of a stable plateau: if one stops learning, practicing, or improving, one’s capacities and virtues atrophy, and one falls behind the demands of life and conscience. In a Hillelite key, “growth” is not merely ambition or accumulation but sustained moral and intellectual cultivation—especially through study, self-discipline, and service to others. The line also carries a warning against complacency: past achievements do not preserve themselves. Its enduring appeal lies in its broad applicability, from education and leadership to spiritual practice, where maintenance requires motion.

1) "He who does not increase, decreases." 2) "If I am not for myself, who will be for me? And if I am only for myself, what am I? And if not now, when?" (often quoted alongside this maxim in the same Hillel passage) 3) "Whoever does not add [to his learning], diminishes."