You focus on the faith of God as though you do not believe what the Bible teaches of man's faith in God that results from hearing and receiving the word of God. All sinners hear the word of God but those who refuse to believe God's word they clearly hear and understand will not have faith because of that hard-hearted willful rejection of the truth. Faith comes after hearing and receiving God's word, not before.Faith is of Grace, its a Gift of God lest any man should boast Eph 2:8
8 For by grace are ye saved through faith; and that not of yourselves: it is the gift of God:
9 Not of works, lest any man should boast.
In Vs 8 the word that is a pronoun and it refers to both Grace and Faith in sync, for both Grace and Faith are not from ourselves, to denote the entirety of Salvation is the Gift of God, so no part of it can give us an reason to boast. We believe because of Grace Acts 18:27
27 And when he was disposed to pass into Achaia, the brethren wrote, exhorting the disciples to receive him: who, when he was come, helped them much which had believed through grace: