This catchy saying used in different lines of work applies in the spiritual realm as well.
Words. Since the tongue is the source of so many of our troubles, it makes sense to limit its use. In general the less we say the less trouble we cause and the more good we accomplish. “He that hath knowledge spareth his words” (Prov. 17:27). Solomon also said that “God is in heaven, and thou upon earth: therefore let thy words be few” and “a fool’s voice is known by multitude of words” (Ecc. 5:2-3). Job’s three friends did more good when “none spake a word unto him” (Job 2:13). They did much less good and far more harm when they started talking (Job 4-25). Less was truly more in their case. Also, Peter said that a Christian woman can influence her non-Christian husband by saying less (I Pet. 3:1-7).
Involvement:  Moses thought the way to help people most was to try to solve all their problems himself (Exod. 18). But his father-in-law told him this was not good and advised him to enlist the help of other men who would help him bear this load. Moses listened to this good counsel and ended up doing more through others by doing less himself. With good intentions preachers make this mistake, thinking they personally have to do whatever needs to be done in a congregation. Elders also make this mistake instead of delegating tasks to others. It may be that there is no one to delegate to; but sometimes we can accomplish more by getting out of the way and letting others get involved.
Numbers. Gideon started with 32,000 soldiers when he prepared for war with the Midianites. God told him, “The people that are with thee are too many for me to give the Midianites into their hands, lest Israel vaunt themselves against me, saying, Mine own hand hath saved me” (Judges 7:2). So God cut the number down to 300! More men would have brought less glory to God and given more attention to human ability; fewer numbers brought more recognition to God and gave less honor to man. God can take a handful of Christians and accomplish more good than we can imagine.
Money. The more money and things you have, the more worry and distractions you have. The more you own, the more you have to occupy your mind and keep your thoughts on this present world. Solomon, the richest and wisest man, said a person can reach the point where the more he has the less he sleeps at night: “the abundance of the rich will not suffer him to sleep” (Ecc. 5:12). Many think that more money means more happiness, but this is not true. In fact, the desire to be rich brings sin and misery ( I Tim. 6:9-10). Also, Americans often think that the way to fix problems and improve situations is to throw more money at them. Has more money made our schools better? Has more government money given people the incentive to work? Has a higher standard of living made us more, or less, spiritual? Less is often more in regard to money and the things it buys.  The less you have, the less worry and distractions you have. The less you have, the more time you can have for God and the more you can look forward to eternity. If we want more of anything, let it be more faith, more love, and more knowledge of God.