Why did Yakov not remove the stone before Rachel arrived?
Seforno: In order not to cause others a loss - should the three shepherds water their flocks before the other local shepherds arrived.
Malbim: His arousal of love for relatives aroused a spirit of strength in him.
What do we learn from the fact that the Torah writes "va'Yagel" (and not 'va'Yegalel')?
Why does the Pasuk repeat "Achi Imo" three times?
Or ha'Chayim #1: To teach us that everything that Yakov did was only because Lavan was his mother's brother, and that it was performed in honor of his mother and not for any other motive.
Or ha'Chayim #2: To remove any suspicion why a [seeming] stranger is helping her. Indeed, in order to avoid this, he made the point verbally with each action.
Tosfos ha'Shalem (8): Even though Lavan was a Rasha, his daughter was [righteous,] like his sister. Even though it was Lavan's flock, it was like his sister's (it did not eat from theft). Lavan had other flocks, Yakov gave to drink only what Rachel tended.
Malbim: It teaches that he helped her due to concern for his relatives' property, and not due to Rachel's beauty.
Ha'Emek Davar: It teaches that he removed the rock, lest his cousin need to wait. He watered the flock, lest his uncle's flock delay (drinking until Rachel waters them).
Why does the Torah say nothing about Yakov drawing water from the well?
Targum Yonasan: No sooner had Yakov removed the stone, than the water began to flow automatically and rose to meet him, and it continued to flow for twenty years, as long as he lived in Charan.