Rom 1:16 For I am not ashamed of the gospel of Christ, for it is the power of God to salvation for everyone who believes, for the Jew first and also for the Greek.
Eph 1:13 In Him you also trusted, after you heard the word of truth, the gospel of your salvation; in whom also, having believed, you were sealed with the Holy Spirit of promise,
Rom 10:9 that if you confess with your mouth the Lord Jesus and believe in your heart that God has raised Him from the dead, you will be saved.
Rom 10:10 For with the heart one believes unto righteousness, and with the mouth confession is made unto salvation.
Rom 10:13 For "WHOEVER CALLS ON THE NAME OF THE LORD SHALL BE SAVED."
May call translates epikalesētai, an aorist tense middle voice subjunctive mood verb. The subjunctive is a potential mood and so conditional—may call or may not call; if they do call they will be saved. Further, one potentially calls for himself/herself since epikalesētai is also in the middle voice. This shows the participation of the subject in the action. Thus salvation is for the masses of humankind, but they respond to God individually, conditionally—may respond (Lavender NT) Psalms _86:5, Isaiah_55:6-7
Act 2:21 AND IT SHALL COME TO PASS THAT WHOEVER CALLS ON THE NAME OF THE LORD SHALL BE SAVED.'
Eph 2:4 But God, who is rich in mercy, because of His great love with which He loved us,
Eph 2:5 even when we were dead in trespasses, made us alive together with Christ (by grace you have been saved),
Eph 2:8 For by grace you have been saved through faith, and that not of yourselves; it is the gift of God,
Eph 2:9 not of works, lest anyone should boast.
As the above verses show we are saved by a gracious God when we believe in His son. That is why the gospel message is to be proclaimed until He comes so that those who trust in the Son will be saved.