Why do rich do people buy expensive car? Isn't it in order for the car to be a testimony of there wealth? Why do the wealthy spend so much money in building a mansion? The mansion is meant to be a testimony of their wealth. So also the Church is the testimony of Christ. Testimony simply means proof or an evident. Christ is spending all that he has on the Church so that she would be a prove of his riches.
"the eyes of your understanding being enlightened; that you may know what is the hope of His calling, what are the riches of the glory of His inheritance in the saints," (Eph 1:18)
The hope of his calling is that we might be the testimony of the riches of his glory. That the world might look at us and declare that Christ is rich in glory. Why is it that when men is placed in an important position, he always wants to declare is status to everybody. Kings drive expensive cars and put their names as the plate number, they declare their status so that all might see. Christ also wants to declare is status so that all might know that he is his the Son of God and he is sited in the right hand of power.
"By this all will know that you are My disciples, if you have love for one another.” (John 13:35)
"that they all may be one, as You, Father, are in Me, and I in You; that they also may be one in Us, that the world may believe that You sent Me. And the glory which You gave Me I have given them, that they may be one just as We are one: I in them, and You in Me; that they may be made perfect in one, and that the world may know that You have sent Me, and have loved them as You have loved Me." (John 17:21-23)
The purpose of the Church is to prove that Jesus is the Son of God and he is sited on the thrown far above every power and authority. Christ wants to showcase his Church to the world in such a way that they would open their mouth in amazement of the wonders of his power and the riches of his glory. The Church is meant to be the testimony of the greatness of Christ.

Let our lives be a testimony of Christ greatness

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