Believing and hearing are an evidence of salvation. You have to see the Son spiritually to believe on Him Jn 6 40
40 And this is the will of him that sent me, that every one which seeth the Son, and believeth on him, may have everlasting life: and I will raise him up at the last day.
The natural man cant spiritually see the Son, in order to believe on Him, because he is dead
Believing and hearing precede salvation
Rom 10:9–10that if you confess with your mouth “Jesus is Lord” and believe in your heart that God raised him from the dead, you will be saved. For with the heart one believes, resulting in righteousness, and with the mouth one confesses, resulting in salvation.
Rom 10:17Consequently, faith comes by hearing, and hearing through the word about Christ.
Eph 1:13–14in whom also you, when you heard the word of truth, the gospel of your salvation, in whom also when you believed you were sealed with the promised Holy Spirit, who is the down payment of our inheritance, until the redemption of the possession, to the praise of his glory.
John 5:24Truly, truly I say to you that the one who hears my word and who believes the one who sent me has eternal life, and does not come into judgment, but has passed from death into life.
Acts 16:31And they said, “Believe in the Lord Jesus and you will be saved, you and your household!”
John 3:16For in this way God loved the world, so that he gave his one and only Son, in order that everyone who believes in him will not perish, but will have eternal life.
Mark 16:16The one who believes and is baptized will be saved, but the one who refuses to believe will be condemned.
1 Cor 15:1–4Now I make known to you, brothers, the gospel which I proclaimed to you, which you have also received, in which you also stand, by which you are also being saved, if you hold fast to the message I proclaimed to you, unless you believed to no purpose. For I passed on to you as of first importance what I also received, that Christ died for our sins according to the scriptures, and that he was buried, and that he was raised up on the third day according to the scriptures,