Final answer:
John 4:12 refers to the patriarch Jacob as the person who drank from Jacob's Well, which he gave to his sons and flocks.
Step-by-step explanation:
According to John 4:12, the individual who drank from the well is referenced as the patriarch Jacob, also known as Israel, who not only drank from the well but had given the well to his sons and flocks. The well referred to in this passage is Jacob's Well, a significant historical and religious site.
In the broader context of the chapter, Jesus is speaking to a Samaritan woman at this well and revealing his identity as the Messiah, drawing a distinction between the physical water of Jacob's well and the living water He provides.