What a shame it is to be without knowledge! ‘Some have not the knowledge of God: I speak this to your shame’ (1 Cor. 15:34). Men think it a shame to be ignorant of their trade, but no shame to be ignorant of God. There is no going to heaven blindfold. ‘It is a people of no understanding: therefore he that made them will not have mercy on them’ (Isa. 27:11)

Watson does not divide doctrine and life:

How many knowledgeable persons are ignorant? They have illumination, but not sanctification. Their knowledge has no powerful influence upon them to make them better. If you set up a hundred torches in a garden they will not make the flowers grow, but the sun is influential.

. . . . . . . . . . .

Many in the old world knew there was an ark, but were drowned because they did not get into it. Knowledge which is not applied will only light a man to hell.

Watson, The Godly Man’s Picture, (BoT, 1666/rp. 1992), 25f.