Can you think of people you may have hurt or offended in some manner?
In Matthew 5: 23-24, Jesus was emphatic about the importance of getting right with those you have offended. "Therefore, if you bring your gift to the altar, and there remember that your brother has something against you, leave your gift before the altar, and go your way. First be reconciled to your brother, and then come and offer your gift."
In other words, Christ was saying, "Don't approach God until you first get right with those you have offended!" Friend, I am not suggesting this is easy, but Christ clearly says it is absolutely necessary. Many Christians lack power because they have ignored this foundational command.
Take the next several moments to consider those you may have offended. When God reveals people you have hurt or slighted, resolve to go to them and ask their forgiveness. Yet, do not go and try to defend yourself or get the battle started again. Just go in simple humility and love. Furthermore, do not think you have failed if they refuse to forgive you. Your responsibility is to do your part in a humble and loving manner. How they respond is their responsibility.
Tremendous miracles occur in families when someone is humbly willing to ask forgiveness for a wrong. Powerful church wide revivals have often hinged on one or two church members getting truly right with one another. We must understand that so called "little" rifts between Christians can easily quench God's Spirit for the whole church! Friend, the Holy Spirit is very sensitive and you must take your relationships seriously.
As we confess and forsake our sins of unforgiveness, we must always remember it is "Christ in us, the Hope of Glory" (Col. 1:27). As believers, we are forgiven and empowered only by the covenant of Christ's blood and His indwelling life. As we plead His precious blood and wholly trust in His fullness, victory is surely ours!