There is a sense in which it may be said that zeal is contagious. Nothing is more useful to the professors of Christianity than to see a real live Christian, a thoroughly zealous man of God. They may rail at him,--they may carp at him,--they may pick holes in his conduct,--they may look shy upon him,--they may not understand him any more than men understand a new comet when a new comet appears;--but insensibly a zealous man does them good. He opens their eyes. He makes them feel their own sleepiness. He makes their own great darkness visible. He obliges them to see their own barrenness. He compels them to think, whether they like it or not--"What are we doing? Are we not no better than mere cumberers of the ground?" It may be sadly true that "one sinner _destroyeth_ much good;" but it is also a blessed truth that one zealous Christian can _do_ much good. Yes: one single zealous man in a town,--one zealous man in a congregation,--one zealous man in a society,--one zealous man in a family, may be a great, a most extensive blessing. How many machines of usefulness such a man sets a going! How much Christian activity he often calls into being which would otherwise have slept! How many fountains he opens which would otherwise have been sealed! Verily there is a deep mine of truth in those words of the Apostle Paul to the Corinthians: "Your zeal hath provoked very many." (2 Cor. ix, 2.) (_c_) But, as zeal is good for the Church and for individuals, so zeal is _good for the world_. Where would the Missionary work be if it were not for zeal? Where would our City Missions and Ragged Schools be if it were not for zeal? Where would our District-Visiting and Pastoral Aid Societies be if it were not for zeal? Where would be our Societies for rooting out sin and ignorance, for finding out the dark places of the earth, and recovering poor lost souls? Where would be all these glorious instruments for good if it were not for Christian zeal? Zeal called these institutions into being, and zeal keeps them at work when they have begun. Zeal gathers a few despised men, and makes them the nucleus of many a powerful Society. Zeal keeps up the collections of a Society when it is formed. Zeal prevents men from becoming lazy and sleepy when the machine is large and begins to get favour from the world. Zeal raises up men to go forth, putting their lives in their hands, like Moffatt and Williams in our own day. Zeal supplies their place when they are gathered into the garner, and taken home.