Both the New Testament and the other Jewish literature describes various Pharisees who seem to have been sincere, honest, and godly. There were certainly those to whom Isaiah 29:13 applied, those who drew near to God with their lips, while their hearts were far from Him.
But there were also those, such as Nicodemus and Joseph of Arimathea, who believed in Jesus and endeavored to follow Him (John 7:50, 19:39, and Mark 15:43).
In Acts 5 we find Gamaliel, the teacher of Paul, arguing for tolerance toward the Christians
On at least one occasion, some of the Pharisees warned Jesus of an attempt on His life, and others are seen showing hospitality to the Lord (Luke 13:31, 7:36, 11:37 and 14:1).
As ideally conceived, Pharisaism was a good thing. There can be no doubt that the Pharisees were the fundamentalists among the normative Judaism of the first century. Josephus wrote,
"The Pharisees are esteemed most skillful in the exact interpretation of their laws."
This may explain why, after the wars of A.D. 66-73 and A.D. 135, when other Jewish sects disappeared, the Pharisees continued, eventually formulating what is known today as Rabbinic Judaism.
(Moseley, Ron. Yeshua: A Guide to the Real Jesus and the Original Church. Hagerstown, MD: Ebed Publications., pgs 110-111)