Technically, “holy” means “without sin,” “pure, morally blameless,” or “set apart” A physical item cannot be sinful or sin-free, as it has no soul and is not human.
As for what is a “church,” that is clearly the Body of Believers in Christ who are meeting. Romans 16:5 says this. The building is not “holy.”
In 1 Corinthians 3:16-17, we learn we are the temple of God.
Are there any insights you can provide to further clarify?
Again when you say how they line up with the Bible, mind you that I always interpret that to mean how “insert person here” that I am talking to interprets the Bible. The 7th Ecumencial Council at Nicea in 787 that the veneration/honor of an image or thing passes to that which it ultimately represents. So the Holy “things” in a Church ultimately point to the Holy Trinity and are Holy because of God. Ultimately this is all rooted back to the Dogma of the Incarnation (the eternal Word[Christ] was incarnate of the virgin Mary and became man]. Christ thus is the image of the invisible God and since Christ became incarnate and had a true human nature with His Divine Nature, sacred images and art and items in a Church thus are appropriate for the faithful to to visually connect to God in their prayer and Liturgical worship of Him.
So the Holy sacred art are tied to Christ who while taking on our human nature, save sin, are what it is rooted to.
So as my Priest said in his homily last night, the Incarnation of Christ where Christ humbled Himself and took on our human nature was to restore us (fallen do to original sin] back to our true nature, our state before God before the fall. So those Saints in Heaven are indeed “Holy” because of God’s grace and thus we honor them how God’s grace has perfected them and we have hope to, due to God’s Grace be among the Holy Saints in heaven as well.
A material item can be made Holy by the power of Christ, Christ himself while having a true human nature, and Divine Nature, was Holy.
Oh and you are welcome, my apologies for not having that in my previous post.