The church, or original Greek, ἐκκλησία (ekklesia), is not an institution, nor is it a proper noun that is capitalized.  This informal term, ekklesia, as it applies to the people of God, in covenant with God, gathered before God, is a congregation or assembly of the “called-out” ones of God at any time on the earth.

In addition, there is a passage in Hebrews 12:22-24 where we read about a vision describing the ekklesia of all the saints in salvation history (OT and NT) gathered in heaven.  This vision meets fulfillment in Revelation 14:1-5.

As it pertains to the assemblies of people on the earth, the ekklesia is comprised of faith-filled believers as well as faith-less unbelievers; all who gather, also known as the church visible.  The formal term for believers in our times is Christian, or, as a group, Christians.

1 Peter 4:16 “But if you suffer as a Christian, do not be ashamed, but glorify God that you bear that name.”

The old covenant (Old Testament) ekklesia was the nation of the twelve tribes of Israel, called out of Egypt to be God’s possession; a people in covenant with God. Many in the old covenant ekklesia were not saved because they were not united by faith with those who listened to the good news (Hebrews 4:2). The Object of faith for the Old Testament saints was the Coming One; the coming Christ who is to bruise the head of the serpent (Genesis 3:15). In Hebrews 11, we learn that Moses regarded disgrace for the sake of Christ as of greater value than the treasures of Egypt, because he was looking ahead to his reward (Hebrews 11:26).

The new covenant (New Testament) ekklesia is comprised of Jew and Gentile, called out of the world to be God’s possession; a people in covenant with God.  Many in the new covenant ekklesia are not saved because they do not understand the word of the kingdom, some fall away because of tribulation or persecution, and others are unfruitful because the cares of the world and the deceitfulness of riches choke the word (Matthew 9:18-22).  The righteous shall live by faith, and those who have faith preserve their souls (Hebrews 10:38-39).  The Object of faith for the New Testament saints is the crucified, buried, and resurrected Christ, Jesus of Nazareth; our coming King (Matthew 25:31-46).

Within the old covenant and new covenant ἐκκλησίαι (ekklesiai) are the saints of God, counted righteous by faith; the sons of Abraham (Galatians 3:7,29).  Together we are made perfect (Hebrews 11:40)—resurrected and caught up at the επιφανειαν (epipheneia), the appearing of the glory of our great God and Savior Jesus Christ; our blessed hope.

The church will not be raptured.  The saints of God, all the saints in salvation history, are resurrected (the dead in Christ first), and then we who are alive, who still remain until the coming of the Lord, are caught up (Gr, αρπαγησομεθα, transliterated harpazō) together with them in the clouds, to meet the Lord in the air (1 Thessalonians 4:16-17).  And we will always be with the Lord.  Therefore encourage one another with these words.