Be zealous.Revelation 3:19
If you want to see souls converted, if you want to hear the cry that "the kingdom of the world has become the kingdom of our Lord,"1 if you want to place crowns upon the head of the Savior and see His throne lifted high, then be filled with zeal. For under God, the way the world will be converted is by the zeal of the church. Every element of grace will do its work, but zeal will be first; prudence, knowledge, patience, and courage will follow in their places, but zeal must lead the charge. It is not the extent of your knowledge, though that is useful, it is not the extent of your talent, though that is not to be despised, it is your zeal that will do great exploits.
This zeal is the fruit of the Holy Spirit: It draws its vital force from the continued operations of the Holy Spirit in the soul. If our inner life dwindles, if our heart beats slowly before God, we will not know zeal; but if everything inside is strong and vigorous, then we cannot but feel a loving urgency to see Christ's kingdom come, and His will done on earth, even as it is in heaven.
A deep sense of gratitude will nourish Christian zeal. When we reflect on the miry pit from which we were lifted, we find plenty of reason for spending ourselves for God. And zeal is also stimulated by the thought of the eternal future. It looks with tearful eyes down to the flames of hell, and it cannot sleep: It looks up with anxious gaze to the glories of heaven, and it cannot stay still. It feels that time is short compared with the work to be done, and therefore it devotes all that it has to the cause of its Lord. And it is continually strengthened by remembering Christ's example. He was clothed with zeal as with a cloak. How swift the chariot-wheels of duty went with Him! He never loitered on the way. Let us prove that we are His disciples by displaying the same spirit of zeal.
1) Revelation 11:15