Romans 10:9-10 That if thou shalt confess with thy mouth the Lord Jesus, and shalt believe in thine heart that God hath raised him from the dead, thou shalt be saved. For with the heart man believeth unto righteousness; and with the mouth confession is made unto salvation.
The word "confess" is the Greek word homologéō (from 3674 /homoú, "together" and 3004 /légō, "speak to a conclusion") – properly, to voice the same conclusion, i.e. agree ("confess"); to profess (confess) because in full agreement; to align with (endorse).
homologéō ("confess") means to speak the same thing, i.e. "assent, agree with, confess, declare, admit" (Vine, Unger, White, NT, 120).
We confess (agree) that Jesus is Lord and we believe in our heart that God raised Him from the dead. We then are saved – Greek sṓzō (from sōs, "safe, rescued") – properly, deliver out of danger and into safety; used principally of God rescuing believers from the penalty and power of sin – and into His provisions (safety).
4982 (sṓzō) is the root of: 4990 /sōtḗr ("Savior"), 4991 /sōtēría ("salvation") and the adjectival form, 4992 /sōtḗrion (what is "saved/rescued from destruction and brought into divine safety").
Romans 10:17 So then faith cometh by hearing, and hearing by the word of God.
God has chosen the foolishness of preaching to save them that are lost (1 Cor 1:21).
When someone preaches to us, we either agree and confess Jesus is Lord, believe God raised Him from the dead, and God delivers us into safety [rescues us from the penalty and power of sin and into His provisions (safety)].
If we disagree with what is preached/heard, we reject God's truth, do not agree or confess, do not believe God raised the Lord Jesus Christ from the dead, and we remain under the penalty and power of sin.