I don't think so.
The 2 Chronicles passage is pointing to humility and repentance of the Israelites being the prerequisite to reversing God's judgment at that time. "Healing the land" in v14 refers to the reversal of the drought, locusts and pestilence mentioned in v13.
Secondly, Jesus often uses hyperbole to make a point. And using that mustard seed analogy in the context of healing a nation is too much of a stretch, in my view.
The 2 Chronicles passage is pointing to humility and repentance of the Israelites being the prerequisite to reversing God's judgment at that time. "Healing the land" in v14 refers to the reversal of the drought, locusts and pestilence mentioned in v13.
Secondly, Jesus often uses hyperbole to make a point. And using that mustard seed analogy in the context of healing a nation is too much of a stretch, in my view.

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