It is not clear how long Joseph was in prison, but we can deduce that the total time of his service to Potiphar and his imprisonment to this point was around 11 years. It had been that long since he was sold by his brothers at age 17, making him about 28 when the same Potiphar, captain of the guard who was over the prison warden, makes Joseph serve Pharaoh's chief butler and chief baker during their confinement. Home may have seemed a distant memory for Joseph by now, given the time he had been away and the trouble in which he now found himself. Being in prison, he was a long way from having his family bow down to himbut he continued to make the best of the situation at hand, and God blessed him for his efforts.
Knowing that God had some big plans in mind, we can assume that these events are His doing. It surely was no accident that two high servants of Pharaoh's court were both placed in the same prison as Joseph. If they had been servants of any lesser government official, one may not have been in a place to later tell Pharaoh about Joseph's gift of interpretation. After hearing the prisoners' dreams, Joseph explains their meaningand the events come to pass just as he foretells. Perhaps after this divine fulfillment, Joseph remembered his own dream, pondering his past and his future.
It actually seems a little hard to believe that the butler, after seeing Joseph's interpretation of the dream come true before his eyes, would actually forget about Joseph's request for a mention to Pharaoh. Perhaps he was so elated to be restored to his high position that he forgot what Joseph had asked of him. Or maybe after getting his job back as chief butler, he didn't want to give someone else the limelight, or perhaps he feared to remind the pharaoh that he had previously sent him to prison. Whatever the reason, God was still orchestrating events to His timetableleaving Joseph imprisoned for another two full years before delivering him, illustrating once again that we should be patient as we wait on God. It may take some time, maybe even a lifetime, but He will come through on His promises.