The Ax Laid to the Root, Parts I & II is unavailable, but you can change that!

Volume 1 contains two sermons on Matthew 3:10, expanding upon the metaphor and applying it to both infant baptism and church membership. Volume 2 contains the second part of Benjamin Keach’s work on Matthew 3:10. The text offers further exposition of the metaphor, a reply to a treatise on paedobaptism, and Keach’s reflections on the work of Joshua Exell.

the Root, whereof he speaks, (as I conceive) was that Covenant God made with Abraham, and his natural Seed, or Off-spring; which Covenant did, in a mystical Sence, as clearly bear up the National Church of Israel, and all the Trees, i.e. Members or Branches thereof, as a common natural Root doth the Tree, or Trees that grow out of it. 2. And as by Root may be meant that Covenant made with Abraham, and his natural Seed, (from whence the National Policy, and Church of the Jews sprang, and was born
Volume 1, Page 5