While it is kind of dry, O Palmer Robertson's Christ of the Covenants.

As to why people disagree:

1) Some would disagree that the covenants expand on each other, but would rather replace each other.

2) Others (Reformed Baptists) would see continuity between the covenants, but would deny the inference that the children of covenant parents receive the sign of the covenant.

From a covenantal argument (granting covenantal continuity), given the overall framework, baptism is an easy follow. But on the other hand, it is often hard to find explicit commands for infant baptism.

That's probably the disagreement.

Others (non-Reformed baptists) would say that if you allow the paedo view of the covenants, and the continuity, then how is the new covenant new?

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J. B. Atken
John Knox PCA
Layman, M.A. student at Louisiana College