If you want to radically change the lives of men and women in low-income neighborhoods, then emphasize the kingdom in your teaching. Over the past few years I've had the opportunity to mentor young people from low-income neighborhoods and broken families. In that work I've found that the biggest conceptual hurdle was not the gospel but helping young people graduate from short-term thinking to long-term thinking. When you have no money and no hope for the future you are likely to spend all of your energy thinking about gratifying desires today.
"Eat, drink, and be merry for tomorrow we die," say the Epicurean. This is motto of short-term thinking. Paul challenges this way of thinking by focusing on the believer's future resurrection (1 Corinthians 15:32). There is more to life than this life. Moreover, our ultimate satisfaction with life cannot even be found in this life but in the one to come for those who are united to Christ.
Jesus teaches us not to store up treasures on earth but to think about our lives in light of heaven (Matthew 6:19-21). In fact, Jesus' teaching on the kingdom (Matthew 6:33) helps condition us to embrace long-term thinking and delayed gratification. We are to seek first the kingdom of God and all that that entails, and rest in the sovereign providence of God for what we need today and tomorrow. This is not only good practical theology, but it also liberates us from the short-term thinking that dominates low-income communities and keeps people from making wise choices.
In Gospel of the Kingdom: Scriptural Studies in the Kingdom of God, George Ladd rightly stresses the importance of the kingdom this way:
"The Kingdom of God is the redemptive reign of God dynamically active to establish his rule among men, and that this Kingdom, which will appear as an apocalyptic act at the end of the age, has already come into human history in the person and mission of Jesus to overcome evil, to deliver men from its power, and to bring them into the blessings of God's reign. The Kingdom involves two great moments: fulfillment within history, and consummation at the end of history."
If the kingdom is not the central theme when working in low-income communities we may not be helping people as much as we think. The ability to practice the virtue and wisdom of delayed gratification in this life is primed to perfection by the gospel of Jesus Christ, which orients our lives toward the priorities of the kingdom to be consummated at the end of history.