The Bible does not speak of dogs, or any other pet going to heaven. Everyone who loves their dog would like to think that their dog would go to heaven because of the love exchanged between them and their pet, but no one knows if dogs will go to heaven or not.
Some people say there is biblical justification to commit to the idea that dogs will go to heaven. But there is not. People confuse heaven with the millennium or the millennial reign of the Lord Jesus Christ. They also confuse heaven with the Paradise that Adam and Eve lived in before their expulsion from it. They consider them to be heaven, but they are not. Both are places on the earth.
What the Pope says about dogs in heaven
The Pope recently said that animals do have souls and are “as near to God as men are”. Unfortunately, animals do not have souls like mankind does. Man is made in God’s image (Genesis 1:26-28). Furthermore, this image comes from the soul that man obtained when God breathed into him the breath of life (Genesis 2:7). No such operation is ever mentioned in the Bible regarding any animal.
In 2023, Pope Francis has also said that his dog will go to heaven. He could not have gotten this from the Bible, because it just isn’t there.
There are certainly animals in paradise. Adam gave them all names there (Genesis 2:18-20). When people confuse paradise with heaven, they conclude that there will be animals in heaven because they assume heaven is paradise.
Jesus will indeed come back to earth, from heaven, riding on a horse (Revelation 19:11), as will His armies (Revelation 19:14). There are the four horsemen of the apocalypse riding on horses (Revelation 6:2, 4, 5, 8) that are in heaven. Therefore, it can be safely concluded there are horses in heaven.
What Isaiah has to say about the subject
The Bible also speaks about the lamb of God (Revelation 5:5) and the lion of the tribe of Judah (Revelation 5:8-9), a dragon (Revelation 12:4, 7, 9), and a beast (Revelation 13:2). There are no other references to anything other than these in heaven.
Some believe Isaiah’s description: “the wolf and the lamb will feed together, and the lion will eat straw like the ox” (Isaiah 65:25) is a reference to heaven, but it is not. It speaks directly to what things will be like in the millennium (Isaiah 11:1-11). Even though the wolf, the bear, the lion, and the lamb will live in harmony in the millennium, this does not address the question, “Will dogs go to heaven?”
In summary, There are animals in heaven, paradise, this present earth, and the millennium. The lack of reference to anything other than horses being in heaven seems that heaven will be absent of all other animals.