We could never see this happening in real-time, but it is happening. A lot of things in life are like that, we can't necessarily see it happening, but we know that it is occurring. Take starting your car for instance; you turn the ignition key and trust that the battery is charged and the spark plugs will fire and that no one has attached a stick of dynamite to your vehicle. This trust when applied to spiritual matters is called faith, but lets just read a few verses from the book of Hebrews:
Heb 11:1 Now faith is the substance of things hoped for, the evidence of things not seen.
Heb 11:2 For by it the elders obtained a good report.
Heb 11:3 Through faith we understand that the worlds were framed by the word of God, so that things which are seen were not made of things which appeared.
Heb 11:4 By faith Abel offered to God a more excellent sacrifice than Cain, by which he obtained testimony that he was righteous, God testifying of his gifts: and by it he being dead yet speaketh. Heb 11:5 By faith Enoch was translated, that he should not see death; and was not found, because God had translated him: for before his translation he had this testimony, that he pleased God.
Heb 11:6 But without faith it is impossible to please him: for he that cometh to God must believe that he is, and that he is a rewarder of them that diligently seek him.
The Webster Bible
Faith: Yes, you can't see it. Yes, you can see the results of it by what you do. Yes, it involves life and death. Yes, Yes, Yes! It is our way of saying, Yes to God! It is the spark of belief, the beginning of hope and the goal of life. It gives light to an otherwise dark and mysterious life. It has been revealed in Jesus and offered to you. The questions is: Will you see what you can't see?