We are continuing the work of the Holy Spirit as it is evident in the church. Now the work of the Holy Spirit is looked at as it evidences itself in the fellowship within the church.
The root of this is Christ Himself. The essence of the church is the body of Christ gathered by Him through all the ages and played out in all of history. He does that through His Spirit who applies God's Word to His people pointing them first and foremost to the knowledge of their sin. In that work of the Holy Spirit we are tied in common...partakers of Christ and all His blessings. You can join many groups or societies today for a common goal or concern, but the church of God has been joined in a common ROOT! Sinners saved by grace and engrafted into Him and although very diverse they are all christians. Note first that we are justified and Holy in the Lord and secondly that there is diversity for the fellowship of the saints and different points of views and they need each other. God puts the body together and tempers it!
Each supplies the necessities of others. We are born with very different gifts that we may use them to benefit others each with a distinct purpose in mind by God Himself! We are challenged here by the catechism to use our gifts and therefore we must first and foremost know who we are in the church of God with our talents and secondly ask how has He made me this way to fit in the church to benefit the whole. He makes us distinct but God always does that for the whole and we must ask ourselves "why did God make me this way for the whole?!" How can someone pray for someone if someone does NOT need prayer? How can one give if there is no one to receive? All gifts are needed and to be used for the welfare of the whole and we must use READILY and CHEERFULLY!
We we ask ourselves these questions then we already understand the purpose is not about my, myself, and I. It is about God's glory! We walk together for His glory and together anticipating final glory! And secondly that we may be together, tempered together to God's glory till we together are in perfect harmony in final glory!