Knowing this first, that there shall come in the last days scoffers, walking after their own lusts, Knowing this first - Considering this in an especial manner, that those prophets predicted the coming of false teachers: and their being now in the Church proved how clearly they were known to God, and showed the Christians at Pontus the necessity of having no intercourse or connection with them.
There shall come - scoffers - Persons who shall endeavor to turn all religion into ridicule, as this is the most likely way to depreciate truth in the sight of the giddy multitude. The scoffers, having no solid argument to produce against revelation, endeavor to make a scaramouch of some parts; and then affect to laugh at it, and get superficial thinkers to laugh with them.
Walking after their own lusts - Here is the true source of all infidelity. The Gospel of Jesus is pure and holy, and requires a holy heart and holy life. They wish to follow their own lusts, and consequently cannot brook the restraints of the Gospel: therefore they labor to prove that it is not true, that they may get rid of its injunctions, and at last succeed in persuading themselves that it is a forgery; and then throw the reins on the neck of their evil propensities. Thus their opposition to revealed truth began and ended in their own lusts.
There is a remarkable addition here in almost every MS. and version of note: There shall come in the last days, In Mockery, εν εμπαιγμονῃ, scoffers walking after their own lusts. This is the reading of ABC, eleven others, both the Syriac, all the Arabic, Coptic, Ethiopic, Vulgate, and several of the fathers. They come in mockery; this is their spirit and temper; they have no desire to find out truth; they take up the Bible merely with the design of turning it into ridicule. This reading Griesbach has received into the text.
The last days - Probably refer to the conclusion of the Jewish polity, which was then at hand.