Glenn McDonald has some interesting insights about what it means to be God’s temple:

The Jesus Movement was launched into a landscape dotted with temples. As followers of Jesus took the Good News around the Mediterranean world, it was impossible not to notice the diversity of sacred spaces.

The Jews of Jesus’ time centered their lives around a single temple in the city of Jerusalem. 
The Greeks, however, built hundreds of temples and shrines, many of them architectural marvels that continue to amaze.  

A temple was a place where heaven met earth.  The ancient Celts spoke of “thin places” – sacred precincts where mere mortals, at least for a few moments, could draw closer to the realm of the gods. Construction was usually undertaken on the tallest hill or ridge in the vicinity – that is, on the acropolis (“high city”).  Athens still boasts what has come to be called the Acropolis, but many Greek cities had a sacred elevation all their own.  

If you intended to worship a particular deity, you journeyed to that god or goddess’ “house.”  It was a place – a destination that occupied actual real estate. It was assumed that the spirit of that deity either lived there or regularly dropped in.  

What happened inside a temple? That depended on whose divine house it happened to be.  
Sacrifices were presented according to the perceived needs of the god or goddess.  Incense might be burned and prayers offered.  Some temples in the Mediterranean world were akin to brothels.  Resident priests or priestesses might declare forgiveness for wrongs committed, or offer guidance concerning future decisions.  There might be secretive rituals of initiation or immersion into an inner circle of true believers.  Security was high.  Access was limited.      

Armed guards might be posted at the threshold, keeping the faithless at bay. Archaeologists have discovered signage from the ruins of ancient Jerusalem that promised swift death to Gentiles who dared to step across the Jews Only perimeter.   

When the apostle Paul’s missionary travels brought him to Corinth, he discovered that the second largest city in Greece was temple-rich. That makes some of his statements to Corinth’s young Christ-followers truly amazing: “Don’t you know that you are God’s temple, and that God’s Spirit dwells in you? …God’s temple is holy, and you are that temple.” (I Corinthians 3:16-17)

We should note that all three “you’s” in those verses are plural. The whole group of men and women following Jesus comprise a living temple where the one true God chooses to live. This idea is equal parts laughable, alarming, and eye-opening.

It’s laughable because, well, think about it: instead of visiting one of the beautiful marble structures where gods and goddesses were typically found, access to the Father that Jesus talks about can happen by spending time with that woman who, with God’s help, is still dealing with the shame of her past, or by encountering that man who sings even the simplest hymns off-key.   

Has God seriously assembled such ordinary people to represent his “house”?  The answer is yes.
The alarming aspect is that it may suddenly dawn on us that we’ve been very confused about a very important idea for a very long time.  Christians routinely speak of going to church, as if God is located at particular piece of real estate we need to visit.  

But Paul is making it clear that God’s temple, the church – the place where he dwells – is us. That means that whenever we are on the move, God is on the move.  

The eye-opening part of this idea is that your day just became much more interesting. Perhaps you were planning on checking your email, picking up a few items at the grocery, and connecting with co-workers.  It’s the same old / same old routine.  

But now you know – in a way that’s hard to put into words – that God’s own Spirit will be at work while you’re checking your email, searching for green beans, and logging onto that Zoom call. Your keyboard and your shopping cart, in other words, are where heaven and earth meet. You don’t need to schedule a trip to the Parthenon to see a really impressive temple. Just look in the mirror.