Does Galatians 3:16 teach that Jesus did not pre-exist?

The "Iglesia Ni Cristo" teaches that Jesus did not pre-exist and they often point to Galatians 3:16 in an attempt to demonstrate this. Is this what Galatians 3:16 teaches?

Galatians 3:16 (ESV) - 16 Now the promises were made to Abraham and to his offspring. It does not say, "And to offsprings," referring to many, but referring to one, "And to your offspring," who is Christ.

When we look at the verse and the claims being attacked, we see that it does not teach that Jesus had no pre-existence.

The humanity of Jesus existed after Abraham.

The biggest problem with this argument is that it demonstrates the INC does not really understand the claims of the doctrine of the Trinity. Trinitarians do not believe that Jesus was eternally a man. Trinitarians believe that Jesus became a man at his conception and birth.

This verse affirms exactly what Trinitarians believe. Humanly, Jesus was an offspring of Abraham. His humanity existed after Abraham.

The person of Jesus existed before Abraham.

The claim of the Trinitarian is rather that the person of Christ existed prior to Abraham. Jesus existed in the form of God prior to his taking on the likeness of sinful flesh. Despite INC denials, we can see this clearly in John 8:58.

Galatians 3:16 does absolutely nothing to counter this claim.

Conclusion

The INC foolishly uses Galatians 3:16 in an attempt to demonstrate that Christ had no pre-existence. The INC reveals that they don't even understand what the doctrine of the Trinity is and then ignorantly argue against it. INC members should repent of their rash argumentation and believe the true gospel.