Actually, it's our Savior who saves us. And note that in Eph 2:8 "faith" is a noun, not a verb. As a noun, it refers to the foundation of what we believe, Jesus as Savior.
I have. Now, your turn. And the verse doesn't say that our faith saves us.
Eph 2:8
For it is by grace you have been saved, through faith — and this not from yourselves, it is the gift of God—NIV
See? We are saved BY GRACE. Which is THROUGH FAITH. By grace, through faith.
2 Peter 2:22
Of them the proverbs are true: "A dog returns to its vomit," and, "A sow that is washed goes back to her wallowing in the mud." NIV
Now, please explain how this verse supports your claim.
But to answer your question, when we no longer have that faith, we are faithless.
Consider 2 Tim 2:13 if we are faithless, he will remain faithful, for he cannot disown himself. NIV
Are you aware that WHEN one believes, they are indwelt with the Holy Spirit, and sealed with Him, FOR the day of redemption, per Eph 1:13,14
13 And you also were included in Christ when you heard the word of truth, the gospel of your salvation. Having believed, you were marked in him with a seal, the promised Holy Spirit, 14 who is a deposit guaranteeing our inheritance until the redemption of those who are God's possession — to the praise of his glory. NIV
So, the Holy Spirit is a deposit to GUARANTEE our inheritance, as God's possession.
These 2 verses are clearly about eternal security. Unless one can find ANY exceptions to this promise. Be my guest.