Reuben (or Reuven, as it is pronounced in Hebrew) was the name of the oldest of Jacob's twelve sons, fathers of the twelve tribes. The Torah records when he was given this name and as well as its meaning. But first a little background information: Jacob had intended to marry Rachel, but was tricked by his father-in-law into first marrying Leah – Reuben's mother. When she gave birth to her oldest, she chose the name Reuben, saying, "Because the L‑rd has seen my affliction, for now my husband will love me." The name is made up of two halves; "re'u" means "look" or "see," and "ben" means "son." Thus, the name Reuben expresses the fact that "re'u" - G‑d saw my needs, and therefore blessed me with "ben" - a son.
Our sages add that Leah chose the name with Divine intuition and was pointing to the contrast between her son, and her mother-in-law's son. "Re'u - see the difference," she said, "between ben - my son, and her son". She was referring to the fact that both Reuben and Esau (his uncle) lost the rights of the firstborn to a younger brother but had reacted very differently. Esau, who had sold his birthright to Jacob, jealously sought to kill his brother. Reuben, on the other hand, did not sell it to Joseph, as it was taken from him against his will, yet did not resent him and even sought to save him in his time of need.
The Chassidic masters teach that the name Reuben refers to "sight," a highly tuned level of G‑dly awareness that is so real that it is as if the person actually perceives G‑d with his own eyes. No amount of argument will convince a person that he did not see something when he did. This experience is unambiguous and definite. The name Reuben expresses certainty and immediacy in our awareness of G‑d.