Across the years, Packer has been involved in theological conversations with Orthodox believers, Roman Catholics, charismatic Christians, as well as mainline Protestants. In each of these encounters, he has promoted a vigorous biblical and spiritual theology, in keeping with the Great Tradition. Packer has been ever mindful of the maxim of Richard Baxter, on whom he wrote his Oxford doctoral dissertation:
in necessariis Unitas,
in non-necessariis Libertas,
in utrisque Caritas.
Despite his charitable spirit and his desire to foster a unitive, irenic evangelicalism, Packer has not been able to avoid controversy. Nowhere have the reactions been more volatile than in the response to Packer’s participation in Evangelicals and Catholics Together. Like his friend Charles Colson, Packer became a major target of the initial evangelical protest against ECT.
Source: Timothy George - "Packer at Ninety", First Things, October 2016, https://www.firstthings.com/web-exclusives/2016/10/packer-at-ninety