When the NT refers to the “faith” of Christ, it is used in the sense of the faithfulness of Christ. Without the faithfulness of Christ there is no basis for our faith. I look at His great faithfulness and not my little faith. I do not look to myself but to Him. He has done so much for all of the human race, manifesting His unconditional love to all. That is the basis of my confidence. In His faithfulness we have a sure anchor for our faith.
“I am, however, alive – but it isn’t me any longer; it’s the Messiah who lives in me. And the life I do still live in the flesh I live within the faithfulness of the son of God who loved me and gave himself for me.” Galatians 2:20 (Kingdom NT)