I have seen churches whose sanctuaries are adorned with banners with phrases and symbols associated with the faith. I have seen banners with a lion, a lamb, a dove, and such like. Does anyone out there remember the 2nd Commandment? Didn't God say not to make any image of anything to represent God? You say, "Matt, those aren't idols: they're just for decoration. Besides, doesn't the Bible itself use these symbols for Jesus and the Holy Spirit?"
Yes, Jesus is called the LION of the Tribe of Judah, and John the Baptist called Him "the Lamb of God" Jesus was an innocent substitute for us on the cross, and He didn't resist when apprehended by the Sanhedrin and the Romans. In that sense, He is a "lamb"....but not literally. In the days of Joshua, each of the Twelve Tribes had its own flag and its own symbol, drawn from prophecies about the Patriarchs. Just like we have the Detroit Lions, Israel had the Judah Lions. ("Judah is a lion's whelp")
Micheal Jordan isn't actually a bull, and Christ isn't really a lion. By way of allegory, C.S. Lewis represented Christ as a lion in The Chronicles of Narnia. I feel we are getting into dangerous territory when we use such symbols to "decorate" our sanctuaries. Is the Holy Spirit a Dove? Fine, He appeared to John the Baptist in that form to identify Jesus as the Christ, and the disciples saw the appearance of flames on the day of Pentecost. But the Holy Spirit is as much a Person as the Father or the Son! He's NOT a bird!
You say, "Matt, you're making too much of it...it's harmless; we don't worship the images." Maybe. I have seen power point slide shows used in displaying the lyrics to worship songs, often accompanied by images of Jesus (as artists imagine Him). So, yeah, you are using an image during worship.
Maybe you think I'm overreacting, But I fear we're getting close to the line, and may have already crossed it. All I can say is, pray and ask the Lord yourselves. Peace.