It is both and more. First confessing is not simply stating or making a claim even if true. The Greek word (homologeō) that has been translated "confess" is not like our English word. We think of confess to state or admit a truth. The Greek word goes further and what we say has to agree in action with what we are saying. To confess Jesus as Lord is to accept Him for all He is by applying that confession to our lives. We are in fact laying down the gauntlet to receive God into our lives as He demands to be. Jesus said this;
Luke 6:46
And why call ye me, Lord, Lord, and do not the things which I say?
In other words just because we might recognize Him as Lord and all that is involved and even confess that (say that) the confession is only true if we allow it to be applied to our lives.
People who confess Him as Lord and do not want to obey all He says (have Him Lord over their lives) are not Christians and will one day be in this number;
Matt 7:21-23
Not every one that saith unto me, Lord, Lord, shall enter into the kingdom of heaven; but he that doeth the will of my Father which is in heaven.
Many will say to me in that day, Lord, Lord, have we not prophesied in thy name? and in thy name have cast out devils? and in thy name done many wonderful works?
And then will I profess unto them, I never knew you: depart from me, ye that work iniquity.
Many a persons want Jesus as Savior, the One who pays for their sins (fire insurance), but few are willing to take Him as Master, King, and Lord of their lives. Only those who surrender to God in Christ, as Lord, which is faith, will be saved.
Keep this in mind. There will not be a single person in Heaven who has not totally surrender to the Lordship of Christ. No one who remains in rebellion in any way to all He is and all God is will be there. That same surrendered spirit is in every true believer who is here. If we cannot look into our hearts and honestly say we are surrendered to God's rule of our lives and we have placed that heart on Jesus Christ then we are not saved. There will be no rebellious hearts in heaven as the only thing that changes after we die will be the body because our hearts have already been changed through repentance towards God and faith in the Lord Jesus Christ at the moment of salvation which is the new birth.
Matt 7:13.14
Enter ye in at the strait gate: for wide [is] the gate, and broad [is] the way, that leadeth to destruction, and many there be which go in thereat:
Because strait [is] the gate, and narrow [is] the way, which leadeth unto life, and few there be that find it.