1 Peter 2:9 is often quoted without any idea who the verse is actually talking about.
1 Peter 2:9 “But ye are a chosen generation, a royal priesthood, an holy nation, a peculiar people; that ye should shew forth the praises of him who hath called you out of darkness into his marvellous light”.
1 Peter 2:10 “Which in time past were not a people, but are now the people of God: which had not obtained mercy, but now have obtained mercy.”
Verse 9 is full of terms defined in scripture as only true Israel. Verse 10 is a quote from Hosea.
Hosea 1:9 “Then said God, Call his name Loammi: for ye are not my people, and I will not be your God.”
This was a temporary punishment for the put away and punished Ten Northern Tribes. This included a promise to become Christians as has happened.
Hosea 1:10 “Yet the number of the children of Israel shall be as the sand of the sea, which cannot be measured nor numbered; and it shall come to pass, that in the place where it was said unto them, Ye are not my people, there it shall be said unto them, Ye are the sons of the living God.”
Those who hate Christ are not His chosen people. True Israel is mostly Christian today. Christ did not fail.