“Ye shall also give unto the priest the first of your dough, to cause a blessing to rest on thy house.” – Ezekiel 44:30, JPS 1917 Tanach
Sforno note the extraordinary way the commandment, “Of the first of your dough ye shall set apart a cake for a gift” (Numbers 15:20) was fulfilled, when Elijah requested of the widow of Zarephath, “make me thereof a little cake first” (1 Kings 17:13, JPS). He promised: “The jar of meal shall not be spent, neither shall the cruse of oil fail” (17:14). And, it was so, for her and her son, as well as Elijah whom she provided for as well (7:15). Thus, we can see the blessings bestowed upon her, for having honored Elijah.
Jewish tradition assigns to Elijah the role of testing others kindness, by asking them to go out of their way to help a stranger, whom is actually Elijah in disguise. In our own lives, we may never know the significance of a unique opportunity to help out others, who depend on our kindness for their very survival. Neither can they reward us, like Elijah rewarded the widow. Yet, G-d will bestow blessings upon us, especially for going out of the way to help others.
The Tree of Life 