Things didn't go exactly as planned. He asked Rivkah for water, and she gave it to him. At this point, she didn't yet mention the camels.
Then it states (24:19), גם ותאמר להשקותו ותכל לשתות כלו אם עד אשאב לגמליך, "When she finished giving water to Eliezer, she said, 'I will also draw for your camels until they finish drinking.'" She didn't mention the camels until Eliezer finished drinking. Why?
The Or HaChaim (24:18) explains that Rivkah acted with greater piety than Eliezer tested for. "Rivkah didn't tell Eliezer immediately that she would give water to his camels, and this demonstrates her generosity. The tzaddekes figured that if she told Eliezer right away that she would draw water for his camels too, he might drink his water very quickly [and he might drink less than he needed to quench his thirst], because he knows that Rivkah still has a lot of work to do, to give water to all the camels. Rivkah didn't tell Eliezer her plans, so he would drink as much as he needed at his own pace. After he finished drinking, she said, 'I will draw for your camels.'
The Shlah found in the parashah another remarkable facet of Rivkah's kindness. After Eliezer finished drinking, it states (24:20), ותמהר הבאר אל עוד ותרץ השקת אל כדה ותער, "She quickly poured out the jug... And she ran to the well..."
The Shlah HaKadosh zt'l (end of Chaya Sara) writes, "After Rivkah gave water to Eliezer, some water was left in the jug, but Rivkah didn't know what she should do with it. If she pours this water for the camels, it will appear like she is comparing camels to humans, for she gives them both to drink from the same utensil. [Giving the same water to Eliezer and then to the animals might indicate that she considers Eliezer and the animals equal.] On the other hand, to pour the water on the ground is disrespectful. It might imply that since Eliezer drank from the water, the water isn't good anymore. Rivkah acted with wisdom. She ran and rushed, making it appear that she accidentally dropped the jug, and the water spilled out due to her haste. This way, Eliezer's honor was upheld."
At the beginning of this episode, Eliezer is called עבד, a slave. For example, it states (24:10, 17), העבד וירץ ...העבד ויקח. Afterwards, Eliezer is called איש (see pasuk 21 and 26, ...משתאה והאיש האיש ויקד). What caused the change?
I heard from a talmid chacham that the change happened when Rivkah called Eliezer אדוני, "my master." As she said (24:18), אדוני שתה, "Drink my master." Eliezer was a slave and wasn't accustomed to people addressing him with much honor. She spoke to him with respect, and this lifted his self-esteem. And since he felt like an איש, the Torah also calls him that way.
Many miracles were performed for Rivkah. For example, it states (24:67), יצחק ויביאה אמו שרה האהלה. Rashi explains, "האהלה ויבאיה, Yitzchak brought Rivkah to the tent, היא והרי אמו שרה, and behold she was like his mother, Sarah... As long as Sarah lived, the candles burned from erev Shabbos to erev Shabbos, there was a blessing in the dough, and a cloud was tied onto the tent. When she died, these miracles ceased. When Rivkah came, these returned."
The water came up on its own to greet her.
The Sidduro Shel Shabbos (1:4:8) adds that there was a blessing in everything Rivkah did. The Sidduro Shel Shabbos proves from the pasukim that Rivkah gave a drop of water to the camels and Eliezer, and it was enough for them because there was a blessing in all her deeds.
We quote, "After the camels drank a little, they stopped drinking." This is because there was a brachah in Rivkah's deeds. A drop of water was blessed in their stomachs, and they had enough. It also states, אל כדה ותער השוקת, that after the slave drank, the jug was still full, like when she gave it to him! Also, it states, גמליו לכל ותשאב, one drawing of water was sufficient for all the ten camels that were with him. And this is all because there was a blessing in everything Rivkah did."
The Sidduro Shel Shabbos (1:4:11) asks, why are the miracles merely hinted at in the Torah, while her deeds of chesed are written in elaboration?
The Sidduro Shel Shabbos answers that the Torah elaborates on the matters we can learn from. When we are told about the miracles she performed, we don't know how to reach those levels. Therefore, there is a greater elaboration on her good deeds, which brought her to those levels.
We can also explain that the Torah elaborates on her gemilus chasadim and not on the miracles that happened to her because gemilus chasadim is the greatest praise! Rivkah wasn't chosen to be Yitzchak's wife because she performed miracles. She was chosen because of her excellent middos.
As Targum Yonason (24:67) writes, עובדהא דחמא בגין ורחמה אמיה כעובדי דתקנן "Yitzchak loved Rivkah because he saw that her deeds were good, like the deeds of Sarah, his mother."
As Reb Yechezkel of Kuzmir zt'l explains, "Hashem performs miracles. The good deeds and the good middos are man's part."
Miracles and Middos in the Shidduch of Yitzchak and Rivkah
Even after Eliezer saw Rivkah performing miracles, he checked whether she had good middos. The Klausenberger Rebbe zt'l says that this proves that one can be a baal mofes (miracle worker) but might still have bad middos.
Several miracles took place when Eliezer sought a shidduch for Yitzchak. Among the miracles were: (1) הארץ קפיצת – the earth jumped for him, and he traveled from Eretz Yisrael to Aram Naharayim in one day. (2) While Eliezer was still davening for the shidduch, Rivkah appeared. (3) The water miraculously rose to Rivkah. (4) The malach switched the plates so Besuel would eat the poisoned food, not Eliezer. The Chidushei HaRim zt'l says that every shidduch involves miracles.
The Kozeglover Rav zt'l explains that the Satan tries to prevent shidduchim from happening because he is aware of the importance and the greatness of shidduchim. Therefore, miracles are part of the process of finding a shidduch, which enables us to overcome the obstacle the Satan puts forth.