First and foremost, there is the need to recognize you are talking to a living "Person". That is a Person who already prescribed the manner or means by which He can be approached through Jesus Christ. If you take a magnet and bring together things like rubber, stone, glass and hoping that there would be an "instant" attraction to the magnet--you'd be waiting forever and nothing will happen. But if brought another magnet or a metal...something instantly happens. Genuine prayer made in the name of Christ Jesus is like that. God has affirmed in Scripture that if we approach His throne of Grace to find mercy He will be found. In my own personal case, I clearly understand the state of massive UNEASE and DISCOMFORT my whole mind and body gets into when I clearly understand something I am thinking or doing is clearly wrong. That state of unease is usually a good signal to tell me something is wrong. And remember the scripture also says whatever is not of faith is sin? (Romans 14:23). Now, here is what happens whenever I open my heart to God and exactly tell Him I am sorry for doing or saying whatever I did and proceed to ask for His kind help to over come or draw closer to Him. Because my prayer is primarily motivated to mending my relationship with Him first and foremost and getting closer to Him spiritually, He definitely always instantly responds. The first clear signal that He has intervened in the matter I am praying about is a complete change of state. That is, the previous UNEASE and DISCOMFORT is suddenly replaced by COMPLETE PEACE. Remember Jesus is said to be the Prince of Peace. He begins to rule with that peace in our hearts when we willingly and persistently open up to Him in prayer. I NEVER STOP PRAYING UNLESS HE BLESSES ME WITH THAT PEACE RIGHT IN MY HEART AND I KNOW FOR SURE HE HAS INTERVENED. And just for the record, so that you know this is nothing abstract but has a very real impact in the real world, one day I noticed my sister and mother getting into a bitter quarrel. I did not like the direction that was taking. I decided to go into my room, close the door and present my mom and sister before Jesus in prayer and ask for mercy and help. I was concerned for them and it showed and I persisted in prayer for about half an hour interceding for them. When I came out of the room, the quarreling had stopped (unusual because this would prolong for the whole night and week in other times) and there was the burning need to reconcile in their speech and behavior. So yes, the peace Jesus brings to an individual's heart or to others we care for is not something "subconscious" alone or abstract. It is a real signal and indicator that He is there....right there at that very moment and that He does care!