Matthew 13:20,21

But he that received—into stony places— The stony, or rocky ground, represents those hearers, who so far receive the word into their hearts, that it springs up in good resolutions, which perhaps are accompanied with a partial reformation of some sins, and a temporary practice of some virtues. Nevertheless, they are not thoroughly affected with the word; it does not sink deep enough to remain in their minds; and therefore, when persecution arises for the sake of the Gospel, and such hearers areexposed to fines, imprisonments, corporal punishments, banishment, and death, or even to any great temptation of an ordinary kind, which requires firmness to repel it, those good resolutions, which the warmth of the passions had raised so quickly in hearing, do as quickly wither, because they are not rooted in just apprehensions of the nature of the Gospel, and in genuine Christian experience; just like vegetables, which, not having depth of soil sufficient to nourish them, are soon burnt up by the scorching heat of the mid-day sun.