If that is what MacArthur actually said, then he is making a sweeping generalization. All of those groups do not view baptism the same way (e.g., there were multiple groups within the Anglican church historically -- Puritans being one of those groups, and they certainly did not hold to baptismal regeneration; the Anglo-Catholic group was a different matter), and all are not squarely in the "baptismal regeneration" camp. In some cases, if they hold to that today, it is because those groups (at least in their mainline form) have been eaten up with liberalism and will believe anything that gives comfort, no matter if it is false. Furthermore, they are not all "Reformed," which is part of the problem. That is in many ways MacArthur's problem too. He holds to the 5 solas/points and such, but he is not Reformed, and the Reformed Baptists on this board would tell you the same thing. He rejects covenant theology in favor of a dispensational model, and that colors the way he looks at things like the sacraments. It could be that Sproul was "surprised" because MacArthur was so "wrong" in his allegation. It sounds more like a "guilt by association" fallacy than anything else.
If we were to follow MacArthur's line of reasoning, one would have to say that to be "truly Reformed" one would have to be an dispensationalist!
First of all, Tim, you must understand that you’re view of baptism did not find definition until the 1500s. Infant baptism was always practiced with the idea of baptismal regeneration in mind. I think that it is no coincidence that the man that helped to spark the Reformation, St. Augustine, both in the lives of Luther and Calvin, also held to infant baptism and baptismal regeneration. Those who point out the error of Tertullian, who also believed in baptismal regeneration though thought it should be done later in life, fail to point out the fact that Origen, who held to infant baptism, also believed in baptismal regeneration. You’re definition of the effects of infant baptism did not come till Zwingli in the 1500s and later Calvin. So, you are correct that the Puritans didn’t hold to baptismal regeneration, but that doesn’t take away what MacArthur stated and simply seeks to take the argument elsewhere. While we can see how the Puritans viewed infant baptism, we can also see how infant baptism came about and whether those who practiced it earliest believed in baptismal regeneration.
Second of all, you’re utter carelessness in regards to MacArthur’s theology is deplorable. I know that many of you on here disagree with MacArthur on many issues, as do I, but to say that he cannot know what a ‘Reformed’ believer ,as yourself, would believe or in what context your understandings of infant baptism were formed. I get VERY tired of many on this bored who just lambast this man just because he holds a different view of eschatology than us, or because of how he views Israel in relationship to the church. To attack this as something which would bar him from discussing baptism with a ‘Reformed’ paedobaptist brother is simply weak and saddening. MacArthur rejects infant baptism because it is NO WHERE to be found in the Bible. You will NEVER find it in the Bible. He brilliantly states that it’s one thing to have disagreements over things that are found in scripture but quite another to have them over things which are nowhere to be found. He also vividly illustrates that baptism and circumcision do not mean the same thing. Just do a search through the Bible of every time that circumcision is used and you will find that it signifies depravity and a need for cleansing and purity. Baptism signifies a believers union with Christ, repentance, and a washing away of that depravity. They are two totally different signs.
I’m not sure if MacArthur discussed this, but can you tell me why Melchizadek was never circumcised? A man who is probably the closest representation of Christ, both a priest and a King (in Jerusalem) whom Abraham gives a tenth of all he has, isn’t circumcised, does this mean that he is not to be incorporated into the Abrahamic Covenant? If circumcision was a seal of the Covenant of Grace why wasn’t it given to other believers such as Melchizadek, Lot, and Shem, who was still alive at this time?
Also, how can you say that Gen. 17 is the Covenant of Grace with circumcision, then simply change the sign with baptism and change those who receive the sign and the time when the receive the sign. The covenant of circumcision is an everlasting covenant, you cannot change the sign but keep the substance, you cannot pick and choose which you will take from this chapter and which you will insert then paste in and then take out.