The fields are ripe for harvest but the workers are few - we have forgotten why He saved us.
"I tell you that out of these stones God can raise up children for Abraham."
You may find Thomas Coke's commentary on this passage most interesting:
Thomas Coke Commentary on the Holy Bible
Matthew 3:9.
Think not to say, — Munster upon this text quotes a remarkable passage from the Talmud, wherein it is said, "That Abraham sits next the gates of hell, and does not permit any wicked Israelite to go down into it." These Jews might perhaps pervert the promise in Jeremiah 31:35-36 to support this vain and dangerous confidence, in opposition to the most express and awful warnings; particularly Deuteronomy 30:19-20. The Baptist, taking his ideas from the objects before him, (as we shall find, in the course of this work, was familiar with our blessed Saviour,) intended to say thus much only to the Pharisees: "I declare it unto you, as a certain and solemn truth, that
God is able, of these very stones, here before your eyes, which he can animate and sanctify whenever he sees fit,
to raise up those, who, though not descended from human parents, shall be,in a much nobler sense than you,
children of Abraham, as being made the heirs of his faith and obedience; and he would sooner work such a miracle as this, than suffer his promise to fail, or admit you to the blessings of his approaching kingdom, merely because you have the abused honour to descend from that holy and favoured patriarch."