Must I confess with my mouth that Jesus is Lord for salvation?
No . The act of confessing Jesus as Lord was a required condition that was part of the Kingdom Gospel. Salvation in the grace gospel today simply requires you to BELIEVE that Christ died for your sins and was raised for your justification. For us today, the act of confessing that Jesus is Lord does not add one iota of value to actually save you. If it was a necessary act to save you, it would become a work, a condition, and it would diminish the 100% grace of the work of Christ on your behalf, (Rom.11:6). The 'confession (profession)' of faith as seen in the verse below is often cited in the wrong context, and misused . The common 'sinner's prayer', and even the Roman Road salvation technique often uses this verse as instruction for a new believer to do in order to be 'saved.' Rom.10:9-10 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. 10 For...