A surrendered heart is crucial in one’s relationship with God, but to use John 14:21 and say that “revelation comes to those who are willing to follow God’s ways” is a plain misuse of the passage, even the context. Jesus is speaking exclusively to His twelve disciples (less one). That promise which He spoke to them was for them, not for any of us today. We are not guided into all truth except through the very written word of God! The apostles did not have for themselves a “Bible” that could be taken into all the world. What they had was God’s Spirit that taught them that which God wanted them to know (1 John 1:1-3; 4:1, 6). This they taught and wrote down for man today (cf. Jude 3).
How does God speak to us today? He speaks to us through His revealed (written) word. This is abundantly clear when one considers the following:
Long ago, at many times and in many ways, God spoke to our fathers by the prophets, but in these last days he has spoken to us by his Son, whom he appointed the heir of all things, through whom also he created the world. (Hebrews 1:1-2,ESV)
To this he called you through our gospel, so that you may obtain the glory of our Lord Jesus Christ. (2 Thessalonians 2:14, ESV)
I hope to come to you soon, but I am writing these things to you so that, if I delay, you may know how one ought to behave in the household of God, which is the church of the living God, a pillar and buttress of the truth. (1 Timothy 3:14-15, ESV)
His divine power has granted to us all things that pertain to life and godliness, through the knowledge of him who called us to his own glory and excellence, (2 Peter 1:3, ESV)
…how the mystery was made known to me by revelation, as I have written briefly. When you read this, you can perceive my insight into the mystery of Christ, which was not made known to the sons of men in other generations as it has now been revealed to his holy apostles and prophets by the Spirit. This mystery is that the Gentiles are fellow heirs, members of the same body, and partakers of the promise in Christ Jesus through the gospel (Ephesians 3:3-6, ESV).
When a man gets into the subjective realm of “God spoke to me” he has gone into a realm that is nothing more than “I want.” In other words, he has gone into a realm where he wants to believe that God spoke to him; it is not a realm of objective truth, but a subjective realm of “This is my opinion and don’t you tell me anything that is different!”
In such a realm, getting the objective truth of God’s revealed word into the mind of that one is difficult. On the other hand, if one is willing to compare his or her subjective approach to life in alongside the revealed word of God (Hebrews 4:12), then the subjective approach can be lain aside for the Lord’s word.
In such case, it can be said, properly, that “God spoke to me.”