Its quite evident from scripture that Faith/believing in Salvation is not something the natural man has, but contrary its by the Grace and Power of God. Paul in his writings always thanked God for the ones that believed or had faith 2 Thess 1:3
3 We are bound to thank God always for you, brethren, as it is meet, because that your faith groweth exceedingly, and the charity of every one of you all toward each other aboundeth;
Col 1:3-4
3 We give thanks to God and the Father of our Lord Jesus Christ, praying always for you,
4 Since we heard of your faith in Christ Jesus, and of the love which ye have to all the saints,
1 Thess 2:13
For this cause also thank we God without ceasing, because, when ye received the word of God which ye heard of us, ye received it not as the word of men, but as it is in truth, the word of God, which effectually worketh also in you that believe.
God the Holy Spirit works effectually causing the elect to believe, so God is Thanked without ceasing
Rom 1:8
First, I thank my God through Jesus Christ for you all, that your faith is spoken of throughout the whole world.
However most believe today that man of himself musters up faith to believe in Christ.