There is a double nature in all believers. Converted, renewed, sanctified as they are, they still carry about with them a mass of indwelling corruption, a body of sin. Paul speaks of this when he says, "I find a law, that, when I would do good, evil is present with me. For I delight in the law of God after the inward man. But I see another law in my members, warring against the law of my mind"(Romans 7:21-23). The experience of all true Christians in every age confirms this. They find within, two contrary principles, and a continual strife between the two. To these two principles our Lord alludes when He addresses His half-awakened disciples. He calls the one flesh and the other spirit. He says, "the spirit is willing, but the flesh is weak."
“Say not, O but my sins are greater than can be forgiven: the difficulties of my salvation are too great to be overcome, especially by a poor creature as I am, that am able to do nothing, no, not to raise one penny towards the discharge of that great debt I owe to God. For here thou wilt find, upon thy union with Christ, that there is merit enough in his blood, and mercy enough in his bowels, to justify and save such a one as thou art. Yea, and I will add for thine encouragement, that it is a righteous thing, with God to justify and save thee, that canst not pay him one penny of all the vast sums thou owest him; when, by the same rule of justice, he condemns the most strict, self-righteous Pharisee, that thinks thereby to quit scores with him. It is righteous for a judge to cast him that has paid ninety-nine pounds of the hundred, which he owed, because the payment was not full; and to acquit him, whose surety has paid all, though himself did not, and freely confess that he cannot pay one farthing of the whole debt.”
By this fear the people of God are excited to, and confirmed in the way of their duty. Eccles. 12:13. Fear God, and keep “his commandments.” It is,the keeper of both tables, because the duties of both tables are influenced by it. It is this fear of God that makes us have a due respect to all his commands, and it is as powerful to confirm us in, as it is to excite us to our duties. Jer. 32: 40. ” I will put my fear into ” their inwards, and they shall not depart from me.” Look as he that sows does not regard the winds, but goes on in his labour whatever weather the face of heaven threatens ; so he that fears God, will be found in the way of his duty, let the aspect of the times be never so lowering and discouraging: and, truly, this is no small advantage, in times of frights and distractions. Slavish fear sets a man upon the devil’s ground, religious fear upon God’s ground : And, how vast an odds is there in the choice of our ground, when we are to endure a great fight of affliction!
Another excellent use of this fear is, to preserve the purity and peace of our consciences by preventing grief and guilt therein, Prov. 16: 6. The fear of the Lord is to depart from evil.” See how it kept Joseph, Gen. xxxix. 9. and Nehemiah, chap. v. 15. And this benefit is invaluable, especially in a day of outward calamity and distress. Look, in what degree the fear of God prevails in our hearts, answerable thereunto will the serenity, peace, and quietness of our consciences be; and proportional unto that will our strength and comfort be in the evil day, and our courage and confidence to look dangers in the face.
T o conclude, a principal use of this fear of God is, to awaken us to make timely provisions for future distresses, that whensoever they come, they may not come by way of surprise upon us. Thus Noah, being moved with fear, prepared an ark,” Heb. 11: 7 I t was the instrument of his and his family’s salvation. Some men owe their death to their fears, but good men, in a sense, owe their lives to their fears; sinful fears have slain some, and godly fears have saved others. A wise man fears and departs from evil, (saith Solomon) but a fool rages and is confident. His fears give a timely alarm before the enemy falls into his quarters, and beat them up; by this means he hath time to get into his chambers of security and rest before the storm fall : But the fool rages, and is confident,” he never fears till he begin to feel yea, most times he is past all hope before he begin to have any fear.