In our study of Ephesians chapter four, we will look at light; its source today and in the future. God is light as we see in 1 John 1:5 and, when we accept Jesus, we are called to be the light in this world (see Matthew 5). We also see, in Revelation 21, that when the heavens and earth are made new God will once again provide light for all of creation.
"As a prisoner for the Lord, then, I urge you to live a life worthy of the calling you have received." NIV translation
We see, in Acts 19, that Ephesus was a very dark place as it was a center of all kinds of satanic things.
Paul begins this letter to the people by urging them to live up to their calling which is to be a bright light in that very dark place.
We have the same calling and it seems that the world today is darker than it has ever been before so this letter is for us as well.
"Be completely humble and gentle; be patient, bearing with one another in love." NIV translation
Paul gets right down to what it means to be the light and it begins with humility. That humbleness comes from the realization that we are nothing and in fact are incapable of anything useful without the grace of God. The second thing is to be gentle in our dealings with those around us even though they may be very difficult and may even being used by the devil. There are varying degrees of light and the degree of light to be used is based on the task just as we have different levels of light in our homes and dimmer switches to control the amount. A big bright light helps us to see a problem and is necessary to point out sin and the need for a savior but a more gentle light is used to encourage and instruct those that know they need the Lord. Paul also reminds us that we are to bear with one another and that is accepting people where they are in their walk with Christ and encouraging them to grow.
Make every effort to keep the unity of the Spirit through the bond of peace. There is one body and one Spirit - just as you were called to one hope when you were called - one Lord, one faith, one baptism; one God and Father of all, who is over all and through all and in all." NIV translation
There is only one God and one hope which is to spend eternity with Him through Jesus Christ. There is only one Spirit that is of God and only one can be in charge (be the light). The only one qualified to be in charge is the Creator of all. If we just allow God to do His will in our lives and the life of the church, then it will function as a unified body.