1. The Ten Plagues
G-d commands Moses to go tell Pharaoh to “Let my people go.” G-d explains that Pharaoh will at first refuse, but after the supernatural events that He brings upon Egypt he will be forced to free them (Source 1).
For three weeks, Moses warned Pharaoh about the impending plague, and for seven days the plague struck Egypt. At the end of the plague, Moses again warns Pharaoh and threatens another plague, and so on (Source 2).
Why, the Rebbe asks, did the plagues and the warnings take so long? Couldn’t a day or two suffice? The warning for the plague of the firstborns was given just once and the plague itself was brief. Why couldn’t that suffice for all the plagues?
Moreover, the Rebbe adds, during these months the Jews had to remain in exile!
2. A Learning Experience
Each plague had a certain effect. For example, the plague of blood crushed the strength of the Egyptian gods, deflated the Egyptians’ pride and raised the self-confidence of the Jews. The frogs deepened the blow to the Egyptian gods because the frogs sprung out of the river to which they ascribed divine power. The lice forced the Egyptian sorcerers to acknowledge the hand of G-d. During the plague of hail, there were some Egyptians who already feared G-d, so they rushed to protect their animals. The locusts made Pharaoh agree to free the men to serve G-d. The same goes for each plague, see at length in the class (Sources 3-8).
The plagues endured for so long in order for the Egyptiansto internalize the effect of each plague. Were the plagues to have been short, and without a break between each plague, the Egyptians wouldn’t have been able to internalize the message of the plagues, and their efficacy would be diminished.
3. The Winning Effect of Time
The Rebbe teaches that when trying to influence others, we may feel that despite our efforts, we weren’t able to make any impact. The story of Pharaoh teaches us that even if the desired result wasn’t apparent—he didn’t free the Jews—still, each plague had an impact. So too, each positive action makes a difference. Sometimes, it can take a while until it is visible.