The first century money changers were in the temple, but they didn't have the spirit of the temple... They were out of sync with the whole purpose of the Lord's house. "The atmosphere of my Father's house," Jesus seemed to say, "is to be prayer. The aroma around my Father must be that of people opening their hearts in worship and supplication. This is not a place to make a buck. This is a house for calling on the Lord.
The Bible does say, "My house shall be called a house of prayer for all nations." Preaching, music, the reading of the Word--these things are fine--but they must never override prayer as the defining mark of God's dwelling.
God nowhere asks anyone to have a large church. He only calls us to do his work, proclaiming his Word to people he loves under anointing power of the Holy Spirit to produce results that only he can bring about.
We have in our churches a great deal of prayer, but I think it would be a good thing if we had a praise meeting occasionally. If we could only get people to praise God for what He has done, it would be a good deal better than asking Him continually for something.
I can say as to myself, that I have been assailed on all sides, and have scarcely been able to enjoy repose for a single moment, but have always had to sustain some conflict either from enemies without or within the church.
Author: John Calvin Source: Preface to the Commentary on the Psalms.
Wherever we find the Word of God surely preached and heard, and the sacraments administered according to the institution of Christ, there, it is not to be doubted, is a church of God.