Jesus purchased the church with His blood (Acts 20:28). The Spirit is given as a pledge until that purchased possession is fully redeemed (Ephesians 1:14). All humankind is not sealed with the Spirit.
Did anyone say "all humankind is sealed with the Holy Spirit?" Nope, of course not. Folks, he just makes it up and posts non-stop falsehoods.
Did anyone say Jesus did not purchase the church with His blood? No of course not. Folks, he just makes it up and posts non-stop strawman evasions.
Born anew Christians will not fall away, out of the hand of God. Nothing can separate us. We did not put us into Christ, and we are powerless to put ourselves out of Christ.
Here the fallacy is to think "he was sanctified" refers to be placed in (within) Christ. But instead, all humankind was set apart (sanctified) under the New Covenant in His blood. When Christ laid down His life as a
ransom for all, He both purchased (bought) all humankind with His blood, He also placed all humankind under the New Covenant in His blood. And of course, included are those placed into Christ, the church of the first born.
Romans 8:38-39
For I am convinced that neither death, nor life, nor angels, nor principalities, nor things present, nor things to come, nor powers, nor height, nor depth, nor any other created thing, will be able to separate us from the love of God, which is in Christ Jesus our Lord.
1Timothy 2:6
who gave Himself as a ransom for all, the testimony
given at the proper time.
2Peter 2:1
But false prophets also arose among the people, just as there will also be false teachers among you, who will secretly introduce destructive heresies, even denying the Master who bought them, bringing swift destruction upon themselves.