The Gemara in tractate Shabbos1 says: “He who is born on a Thursday will be a benevolent individual, for on that day, the fish and birds were created,”2 i.e., on that day — as Rashi explains3G‑d created beings that are wholly sustained by His kindness.

The Gemara, however, informs us in another tractate4 that all Jews are by nature compassionate and benevolent.5 This being so, what is special about the Jew born on a Thursday, as compared to Jews born on other days of the week?

The fifth day of Creation was unique, since on that day, as Rashi explains, G‑d’s benevolence was dominant — a benevolence that is boundless, for just as G‑d Himself knows no limitation, so too are His attributes limitless.

Indeed, because His boundless benevolence was dominant on the fifth day, the beings created on that day — especially fish — multiply greatly.

Herein lies the difference between all Jews’ natural benevolence and the benevolence of one born on a Thursday: The degree of most Jews’ natural kindness is limited — they will act kindly toward others, but not to the extent of foregoing all their own needs or undergoing excessive hardship.

However, he who is born on that day when G‑d’s kindness was manifest will display a natural tendency to completely disregard his own being in order to assist others.

Conversely, there is special merit to the innate kindness found within all Jews, as opposed to the capacity for kindness and benevolence evinced by those born on a Thursday.

Understandably, being born on a Thursday does not guarantee that a person will be infinitely kind; it simply means that he or she will have a slightly stronger inclination to act kindly, and that this kindness — if fully realized — can be boundless.6 However, the benevolence inherent in every Jew’s character is an actual goodness — not just the Thursday-type potential for goodness and benevolence.

For a person to aspire to infinite benevolence, he must first possess the quality of self-effacement; as long as a person thinks primarily of himself, it will be impossible to give totally of himself to others. Diminishing one’s own ego and desires enables one to become immersed in the act of kindness — a kindness not confined by a sense of self, but a kindness without end.

This aspect of self-nullification is also alluded to by the creation of fish on the fifth day. Fish, which multiply greatly — indicative of an infinite capacity — are entirely covered by water. As such, they are completely hidden from our view; all a person sees is the water.

Water is, of course, a fish’s source of life. Being so completely immersed in one’s source that all others see is the source, alludes to complete self-nullification — a quality that leads to the blessing of, and the capacity to, multiply without limit.

So too regarding man’s manner of service. In order to arouse the loftiest degree of benevolence — which is similar to G‑d’s boundless kindness — a person must first nullify himself before G‑d. This will cause him to become truly humble, and enable him to perform boundless kindness, free of the constraints of self.

This is also the intent of Rashi’s comment to the verse7 “Cleave to Him,” where he notes:8 “Cleave to His ways, perform acts of benevolence … just as G‑d does.”

When a Jew is truly cleaving to G‑d, feeling only the A-mighty and himself not at all, then he can rest assured that his acts of kindness will emulate G‑d’s — he too will perform acts of boundless benevolence.

Based on Likkutei Sichos, Vol. XXV, pp. 10-12