In a sermon entitled “The Happiness of Fearing Alway,” Thomas Boston spoke of the need to fear oneself:

Happy is he that feareth alway with respect to himself. Every man is his own nearest neighbour, and so his worst enemy is nearest to him. Happy is the man that keeps a jealous eye over himself. “Only take heed to thyself, and keep thy soul diligently, lest thou forget the things that thine eyes have seen, and lest they depart from thy heart all the days of thy life.” And there are four things about yourselves which you have need to fear; to be jealous over them, and circumspect about them, lest you offend God in them and by them.

Thomas Boston, The Whole Works of Thomas Boston: Sermons, Part 1, ed. Samuel M‘Millan, vol. 3 (Aberdeen: George and Robert King, 1848), 7.

We should fear our heads, our hearts, our tongues, our senses.

We should fear our heads, lest we become prey to bad ideas, “God is a God of truth as well as holiness. There are soul ruining principles as well as practices.” There were bad ideas infecting minds in Boston’s day, but I’m willing to venture that we have increased the stock of soul-destroying concepts. We should be willing to question what we know or think.

We should fear our hearts: “The heart is the principle of action as the eye is the light of the body. Great need then is there for the heart to be pure. O! what need to entertain this holy fear with respect to the heart; for it is deceitful above all things and desperately wicked. If you would have the streams pure you must look well to the fountain.”

Our heart too easily and too willingly fastens upon the wrong objects, upon those thing which debase and shame. Conversely, godly affections too easily dissipate, “Good affections are tender buds of heaven easily checked and made to wither; and bad ones like ill weeds grow apace.”

We should fear our tongues. “It is dangerous to ride on an unbridled horse, and equally dangerous to have an unbridled tongue.” More damage has been wrought by the tongue than by hand; often the worst acts of violence are stirred up by the tongue. And the tongue has destroyed countless lives before death has taken the body.

We should fear our senses. At this point Boston sounds very much like John Bunyan in The Holy War: the senses are gates to a city, and thus the means which Satan gains entrance to the heart: “These are the gates of the soul, and when the town is besieged, there must be strict watch kept at the gates. Satan lays his trains at these gates, and if we do not take good heed, the whole soul may be set on fire. By the eyes and the ears, did the devil blow up all mankind in Adam and Eve.”