That scripture says:
How do you discern if someone has the mind of Christ or not?
And, again, you have not yet answered these questions:
Do you think an "eternally saved" person will go his whole life, even until death, totally ignorant about the righteousness of God, revealed in the gospel? Can an "eternally saved" person believe false gospels, damnable heresies and be a worker of iniquity all his life, and die in that state, and yet be among the "eternally saved"? All that signifies that they are among the "eternally saved" is a zeal for their beliefs and their god?
How do you discern if someone is regenerate or not? Do saved people have any certain marks as how to what they believe and teach and live their lives or is just about anyone who professes interest in God, religion, the Bible, morals etc (however false it would ever be) among the "eternally saved"?
Do you see where your reasoning leads to?!?!