Upvote:8
Since God created only the man and the woman, not animals, in His image, you are correct in saying that for God to become an animal would be against His nature.
That is not to say that God never used animals to accomplish his will. The classic illustration is found in Numbers, Chapter 22. God was angry with the prophet Balaam, and the angel of the LORD (a pre-incarnate appearance of Jesus Christ?) let Balaam know via his donkey that he was headed for disaster. Because Balaam was intent on disobeying God, he was not aware of the awesome presence of the angel of the LORD, but his donkey was! Not until Balaam had beaten his poor donkey three times did God open Balaam's eyes to the danger he faced.
My point is that God does not despise animals, or treat them with contempt. On the contrary, He cares for them. The last verses of the book of Jonah tell us the reason God refused to destroy Ninevah was out of concern for both its citizens and its many animals (4:10-11)!
As for trinitarians, of whom I am one, they believe God in eternity past had a plan to rescue the human race from sin. In the eternal counsels of the Triune God, the Godhead determined that the Savior of humankind would be God's only beloved Son, who at the fulness of time was conceived by the Holy Spirit, born of the virgin Mary, born under the Law that he might redeem those who were under the curse of having broken God's Law.
In conclusion, the redemption of humankind could have been achieved by no other means than by the death of Jesus Christ, whom the Bible has revealed to be both the lion of the tribe of Judah, and the Lamb of God who takes away the sin of the world. The lion and the lamb are metaphors, of course, but God chose them to be symbols for His Christ. The lion speaks of the ferocity of the Christ, who will execute judgment on rebellious and unrepentant mankind in the great and awesome Day of the Lord.
The lamb speaks of God's perfect sacrificial Lamb, who was led to the slaughter, willingly and silently, and who by the shedding of his blood made cleansing from sin and forgiveness possible for those who believe.