Adam Clarke on 2 Thessalonians 1:3

Your faith groweth exceedingly - The word ὑπεραυξανει signifies to grow luxuriantly, as a good and healthy tree planted in a good soil; and if a fruit tree, bearing an abundance of fruit to compensate the labor of the husbandman. Faith is one of the seeds of the kingdom; this the apostle had sowed and watered, and God gave an abundant increase. Their faith was multiplied, and their love abounded; and this was not the case with some distinguished characters only, it was the case with every one of them.