Even the ability to come to Christ in faith is a gift based upon the cross of Calvary. At the cross, Christ purchased for His people the Grace to believe in His name Phil 1:29

29 For unto you it is given in the behalf of Christ, not only to believe on him, but also to suffer for his sake

Gal 6:14

14 But God forbid that I should glory, save in the cross of our Lord Jesus Christ, by whom the world is crucified unto me, and I unto the world.