"Remain in me, and I will remain in you. No branch can bear fruit by itself; it must remain in the vine. Neither can you bear fruit unless you remain in me. I am the vine; you are the branches. If a man remains in me and I in him, he will bear much fruit; apart from me you can do nothing." John 15:4-5. The way we abide is through obedience to His words. The best ministry preparation we can have is to draw close to Christ and live in obedience and dependence upon Him. He alone makes ministry worth the effort.
Paul wrote: "Not that we are competent in ourselves to claim anything for ourselves, but our competence comes from God. He has made us competent as ministers of a new covenant--not of the letter but of the Spirit; for the letter kills, but the Spirit gives life." 2 Cor. 3:5-6. He also wrote, "I can do all things through Christ who strengthens me." (Phil. 4:13).
Drawing upon the Spirit: "The Spirit gives life; the flesh counts for nothing." We can and should make the Gospel clear, so that people can love God with their minds, as well as with their heart, soul and strength. God uses instruments to evangelize (Romans 10:14-15). But we cannot save anyone. Perhaps the greatest difficulty you will encounter while witnessing is indifference. Without the conviction of sin, people will not sense a need for God or for any personal remedy. "When he [Spirit] comes, he will convict the world of guilt in regard to sin and righteousness and judgment." (John 16:9).
We are introducing people to a Person. We are not introducing people to a plan of salvation, or to an evangelistic program, or to a church or even to us—but to the Person of God. Who would you like to introduce to Christ?
The heart of ministry is relationships. This is how God relates to us, and how we are to relate to others. "If I speak in the tongues of men and of angels, but have not love, I am only a resounding gong or a clanging cymbal." (1 Cor. 13:1).
A personal, genuine relationship with Christ is the criteria for whether or not we have eternal life. "He who has the Son has life; he who does not have the Son of God does not have life." (1 John 5:12, NIV).
"Many will say to me on that day, 'Lord, Lord, did we not prophesy in your name, and in your name drive out demons and perform many miracles?' Then I will tell them plainly, 'I never knew you. Away from me, you evildoers!'" (Matt. 7:22-23). This word "knew" means a personal, experiential knowledge, not a simple knowledge about something.
King David drew his strength from the Father.
"From the ends of the earth I call to you, I call as my heart grows faint; lead me to the rock that is higher than I. For you have been my refuge, a strong tower against the foe." Ps. 61:2-3
"Find rest, O my soul, in God alone; my hope comes from him. He alone is my rock and my salvation; he is my fortress, I will not be shaken." (Ps. 62:5-6)
"Because you are my help, I sing in the shadow of your wings. My soul clings to you; your right hand upholds me." (Ps. 63:7-8).
When we become tired, fatigued, worn out, discouraged, or forgetful of where the power is, we need to return to the source of our power, re-connect with God. He can speak power into us, bring conviction of sin, give protection, give a sense of conviction of sin, draw people to Himself—and we can't.
Why did Christ spend so much time alone with His Father in prayer, in lonely places? If we lose fellowship with God, we lose the power of God and we lose the proper focus of ministry. The Spirit wrote to the Ephesian Church: "I know your deeds, your hard work and your perseverance. . . You have persevered and have endured hardships for My name, and have not grown weary. Yet I hold this against you: You have forsaken your first love. Remember the height from which you have fallen! Repent and do the things you did at first." (Rev. 2:2-5). A ministry without love for God and love for people is a hollow parody of the Gospel.
This ministry begins with abiding in Christ, is empowered and sustained by the Trinity, and finds life through love.