Man and animals were created by God in much the same way. Both were formed from the dust. When God breathed into the man His "breath of life," the man became a "living being." The word used in the Hebrew text is nephesh, which means "soul" or "sentience." Man became a nephesh.
Yet this is not the first time the word nephesh occurs in the Bible. The first time was when God created animals—He gave them the "breath of life," which also made them nephesh.
"And to all the beasts of the earth and all the birds in the sky and all the creatures that move along the ground—everything that has the breath of life in it—I give every green plant for food” (Genesis 1:30).
Interestingly, the word for plant, which is also a living organism, was not the same as the one used for man and animals. Only man and animals were given the breath of life. King Solomon, the wisest man who ever lived, let us know that, "all have the same breath; humans have no advantage over animals" (Ecclesiastes 3:19). It is God’s breath that gave man his nephesh, or soul; therefore, it is reasonable to conclude that animals, too, have souls.
Another strong indicator that animals have souls occurs in Genesis 9. In addition to being co-signatories to God's life-assuring covenant after the Flood, animals were given something else in common with man: accountability. In Scripture, God warned both men and animals that neither must ever kill a human being.
“And for your [man’s] lifeblood I will surely demand an accounting. I will demand an accounting from every animal. And from each human being, too, I will demand an accounting for the life of another human being” (Genesis 9:5-6).
From this passage, we can infer two things. First, we can presume that animals have souls, because in the afterlife, God said He would demand a reckoning from any creature—human or beast—that takes the life of a person.
Second, we can surmise that animals have been given a kind of moral compass. God created a standard of behavior for animals. Whatever other commands they must follow (which we humans may not be privy to), God has told them that humans must never be killed—and any creature who commits this sin will be held liable. Therefore, God must have imprinted a type of law on their hearts.
Before the start of his ministry, the Holy Spirit sent Jesus out into the wilderness to be tempted by Satan. During that time, he was in the presence of wild animals—and yet he wasn’t torn apart by them. Animals are widely thought to be creatures of mindless instinct, but they too will obey the code given to them by God. Jesus was not attacked by the wild animals, who might have been as hungry as he was, but instead they respected him and did him no harm. It is yet another reminder that humans and animals are both created things, and both answer to their Creator.
Surely the fate of human beings is like that of the animals; the same fate awaits them both: As one dies, so dies the other. All have the same breath; humans have no advantage over animals. Everything is meaningless. (Ecclesiastes 3:19)
“And for your lifeblood I will surely demand an accounting. I will demand an accounting from every animal. And from each human being, too, I will demand an accounting for the life of another human being. Whoever sheds human blood, by humans shall their blood be shed; for in the image of God has God made mankind.” (Genesis 9:5-6)
“And he was in the wilderness forty days, being tempted by Satan. He was with the wild animals, and angels attended him." (Mark 1:13)