Complete Commentary on the Whole Bible, by Matthew Henry, at sacred-texts.com
(Sa1 27:1-7) David retires to Gath.
(Sa1 27:8-12) David deceives Achish.
Unbelief is a sin that easily besets even good men, when without are fightings, and within are fears; and it is a hard matter to get over them. Lord, increase our faith! We may blush to think that the word of a Philistine should go further than the word of an Israelite, and that the city of Gath should be a place of refuge for a good man, when the cities of Israel refuse him a safe abode. David gained a comfortable settlement, not only at a distance from Gath, but bordering upon Israel, where he might keep up a correspondence with his own countrymen.
While David was in the land of the Philistines, he attacked some remains of the devoted nations. The people whom he cut off were long before doomed to destruction. It is often wisdom to shun public notice, but we must in no situation be idle. We must always try to do somewhat in the cause of God. This expedition David hid from Achish. But an equivocation which serves the purpose of a lie, is as like to it as a hypocrite is to a profane person, it is only better in appearance, therefore more dangerous. Yet, though believers often manifest imperfections, they can never be prevailed upon to renounce the service of God, and to unite interests with his enemies, or finally to become the servants of sin and Satan. But what a train of evils follow from unbelief! When we forget the Lord's past mercies, and his gracious assurances, we shall be overwhelmed with desponding fears, and probably be led to adopt some dishonourable method to get rid of our troubles. Nothing can so effectually establish us in holy tempers and practices, and preserve us from perplexities, as firm, unshaken dependence upon the promises of God in Christ Jesus.