Yet hath he not root in himself, but dureth for a while: for when tribulation or persecution ariseth because of the word, by and by he is offended.
Ver. 21. Yet hath he not root in himself] These flashy affections have not principles to maintain them, and therefore come to nothing. They are enlightened only as by a flash of lightning, and not by the sunbeam; they do no more than taste of the good word of God, as cooks do of their sauces, they let nothing down, they digest it not, Hebrews 6:4,5 "A good man is satisfied from himself," saith Solomon, Proverbs 13:14; hath a spring within his own breast. Hic sat lucis, This is of light, said Oecolampadius, clapping his hand upon his heart. This the temporary cannot say; he is moved by some external principle, as are clocks, windmills, and the like: "the root of the matter is not in him," Job 19:28. He lacks depth of earth. ουκ εβαθυνε, saith another evangelist, the plough hath not gone deep enough; and therefore, though the earth be good, and the seed good, yet being uncovered, unburied, it miscarries. Exoriuntur, sed exuruntur, " His roots are dried up beneath, and above is his bud cut off," Job 18:16 .
For when tribulation or persecution ariseth] As it will, for ecclesia haeres crucis, saith one. And opposition is evangelii genius, saith Calvin. It is but a delicacy to go about to divide Christ and his cross.
By and by he is offended] Vadat Christus cum suo evangelio, saith he. Let Christ keep his heaven to himself, if it can be had upon no other terms: he is resolved to suffer nothing. When it comes to that once, he kicks up profession, and may possibly prove a spiteful adversary of the same ministry which he once admired, as Herod; and a proud condemner of the same remorse with which himself was some time smitten, as Saul. Crystal seems a precious stone, till it come to the hammering.