Man cannot by His own freewill come to Jesus Christ or believe on Him for Salvation. Its all of God to cause the man or women to believe in Christ Jn 6:44. God must draw the person, or cause the person to believe in Christ, for its written 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;
Thats part of the drawing, to be given to believe on Him. Its given not on behalf of mans freewill, but on behalf of Christ. Also in the drawing, the causing to believe in Christ certain spiritual blessings are given #1 Spiritual eyes will be open to see Christ spiritually 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.
#2 Will be given spiritual ears to hear His voice. Men naturally are spiritually dead and deaf and cannot hear with understanding Jn 8:43
43 Why do ye not understand my speech? even because ye cannot hear my word.
In believing in Christ via the Gospel it requires some spiritual understanding Matt 13:23
23 But he that received seed into the good ground is he that heareth the word, and understandeth it; which also beareth fruit, and bringeth forth, some an hundredfold, some sixty, some thirty.
Naturally man doesnt have this understanding Rom 3:11
There is none that understandeth, there is none that seeketh after God.
And this word understandeth is the same greek word for understand in Mat 13:23. Now in drawing to Christ its given to see Him Spiritually and hear Him spiritually with spiritual understanding. 14