The power a Christian (and the Church by extension) has is PRAYER. The list below gives quick reference to PRAYER as found in the epistles. Many of them can stand alone in understanding but it always profitable to put them into their surrounding text. All text are from Kings James Version (KJV).
Romans 10:1 Brethren, my heart’s desire and prayer to God for Israel is, that they might be saved.
Romans 12:12 Rejoicing in hope; patient in tribulation; continuing instant in prayer;
1 Corinthians 7:5 Defraud ye not one the other, except it be with consent for a time, that ye may give yourselves to fasting and prayer; and come together again, that Satan tempt you not for your incontinency.
2 Corinthians 1:11 Ye also helping together by prayer for us, that for the gift bestowed upon us by the means of many persons thanks may be given by many on our behalf.
2 Corinthians 9:14 And by their prayer for you, which long after you for the exceeding grace of God in you.
Ephesians 6:18 Praying always with all prayer and supplication in the Spirit, and watching thereunto with all perseverance and supplication for all saints;
Philippians 1:4 Always in every prayer of mine for you all making request with joy,
Philippians 1:19 For I know that this shall turn to my salvation through your prayer, and the supply of the Spirit of Jesus Christ,
Philippians 4:6 Be careful for nothing; but in every thing by prayer and supplication with thanksgiving let your requests be made known unto God.
Colossians 4:2 Continue in prayer, and watch in the same with thanksgiving;
1 Timothy 4:5 For it is sanctified by the word of God and prayer.
James 5:15 And the prayer of faith shall save the sick, and the Lord shall raise him up; and if he have committed sins, they shall be forgiven him.
James 5:16 Confess your faults one to another, and pray one for another, that ye may be healed. The effectual fervent prayer of a righteous man availeth much.
1 Peter 4:7 But the end of all things is at hand: be ye therefore sober, and watch unto prayer.