The Church as the body of Christ comprises people who have a common bond and share life expressed in fellowship (koinonia) which is the basis and ground for mutual association and expression of the Christian relationship. Unfortunately the Church is also divided on the basis of certain factors such as nepotism and power struggle. Though this divisive situation was alien to the Sudan Interior Mission (SIM) that gave birth to Evangelical Church Winning All (ECWA), it has characterised ECWA, especially ECWA Ilorin District Church Council (IDCC) through some decades of its existence. IDCC has witnessed unity in recent years, which if guarded could be strong and durable. The main aim of this study was to examine the sustainability of unity on ECWA IDCC in the light of Philippians 2:1-11. The objectives of the study were to: (i) investigate the causes of disunity and conflicts in IDCC; (ii) assess the place of unity among SIM/ECWA missionaries and early converts of the church; (iii) do an exegetical analysis of Philippians 2:1-11 with the aim of understanding the literal and theological meanings of the self-abnegation of Christ; (iv) point out the relevance of Christâ€™s humility to the promotion of unity in ECWA IDCC; and (v) educate members of ECWA IDCC on continuous sustainability of unity in the church. rnThe research methods adopted in this thesis were historical and exegetical. The historical method provided biblical and denominational records of events. The employment of exegetical method was to explain some critical biblical expressions, particularly Greek, for the right interpretation and correct applications of relevant texts to the issue of church unity. rn The findings of this study were that: rni. conceit, sectionalism, nepotism and power tussle based on ethnic diversity were allowed to breed rivalry and jealousy in IDCC;rnii. unity among SIM/ECWA missionaries and early converts was achievable because both lived up to their profession of a common bond in Christ Jesus;rniii. self-abnegation of Christ is not self-disparaging but an antithesis of pride, self-conceit and selfishness that is crucial to good human relationship;rniv. special endowment is a factor in the promotion of unity by paying indiscriminate attention to the needs of others as Jesus selflessly did despite his exalted position; andrnv. ECWA IDCC members are taught on the need to live in and sustain unity through programmes such as joint fellowship, joint board of eldersâ€™ meeting, central choir, and IDCC conference.rnThe study concluded that unity is the bedrock of progress and harmonious co-existence in any organization. Disunity comes if such an organization loses focus and allows crises to grow unchecked because unimportant things have been given prominence over the important. But the desire of Jesus is that the church should be one and this should be the passion of every Christian, leader or follower. The study recommended that the leaders and members of ECWA IDCC needed to live in and sustain unity among themselves by following after the example of Jesus.