John 6:64,65

‘But there are some of you who do not believe' (for Jesus knew from the beginning which of them did not believe, and who it was who would betray him). And he said, “That is why I told you that no one can come to me unless it is given to him by the Father”.'

But Jesus knew that among His wider group of disciples were some who did not truly believe. They had their own motives for following Him. So once again Jesus recognised the sovereign work of the Father in the salvation and destiny of men. All are given the opportunity, but not all will come. Judas especially was given the opportunity, but he turned it down to further his own ends. Yet, although this would be because of their own free choice, for men are free to reject Him if they will, in the final analysis it would be because it was not granted to them by the Father overriding their rejection. The truth is that without God's work of grace no one would be saved.