Bahá’u’lláh wrote:

“…The light of men is justice.  Quench it not with the contrary winds of oppression and tyranny. The purpose of justice is the appearance of unity among men…”
(Tablets of Bahá’u’lláh, p. 66-67)

“Justice, which consisteth in rendering each his due, dependeth upon and is conditioned by two words: reward and punishment. From the standpoint of justice, every soul should receive the reward of his actions, inasmuch as the peace and prosperity of the world depend thereon, even as He saith, exalted be His glory: “The structure of world stability and order hath been reared upon, and will continue to be sustained by, the twin pillars of reward and punishment”.
(The Tabernacle of Unity, p. 40)

“The best beloved of all things in My sight is Justice; turn not away therefrom if thou desirest Me, and neglect it not that I may confide in thee. By its aid thou shalt see with thine own eyes and not through the eyes of others, and shalt know of thine own knowledge and not through the knowledge of thy neighbor. Ponder this in thy heart; how it behooveth thee to be. Verily justice is My gift to thee and the sign of My loving-kindness. Set it then before thine eyes.”
(The Hidden Words of Bahá’u’lláh, Part I – From the Arabic, # 2)

“Whoso cleaveth to justice, can, under no circumstances, transgress the limits of moderation…”
(Gleanings from the Writings of Bahá’u’lláh, p. 342)

“It beseemeth you to fix your gaze under all conditions upon justice and fairness…”
(Tablets of Bahá’u’lláh, p. 36)

“…And if thine eyes be turned towards justice, choose thou for thy neighbour that which thou choosest for thyself…”
(Tablets of Bahá’u’lláh, p. 64)