Mocking unbelievers will often say something like, “Brainwashed Christians just have blind faith in their invisible sky god. Why doesn’t God just come down and show Himself if He exists? Then there would be actual proof of Him, and there would be no need to blindly believe.” It’s the same sort of thinking that crucified the Lord:
“He saved others; himself he cannot save. If he be the King of Israel, let him now come down from the cross, and we will believe him,” Matthew 27:42
Unbelievers who refuse to accept Jesus Christ as their savior and who often deny God’s existence have refused God, and so haven’t had an encounter with Him.
Anyone who has, though, can understand why faith in Him is necessary.
It’s a paradox, but having faith makes a person both dependent on and independent of God at the same time. The more a person is dependent on Him by faith, the more independent of Him, in at least one way, he or she can be. Because born-again believers have the Son of God living within them, and so are guided by the Holy Spirit and are growing in grace and obedience to Him, they increasingly do the Lord’s will before their own, and don’t need God always standing over them or coercing them to do what He wills. It’s almost like a boss who leaves for a time, and while he’s away, some workers will work, believing in what they’re doing, and others won’t, thinking they’re safe because the boss is away.
“Watch therefore: for ye know not what hour your Lord doth come. But know this, that if the goodman of the house had known in what watch the thief would come, he would have watched, and would not have suffered his house to be broken up. Therefore be ye also ready: for in such an hour as ye think not the Son of man cometh. Who then is a faithful and wise servant, whom his lord hath made ruler over his household, to give them meat in due season? Blessed is that servant, whom his lord when he cometh shall find so doing. Verily I say unto you, That he shall make him ruler over all his goods.
“But and if that evil servant shall say in his heart, My lord delayeth his coming; And shall begin to smite his fellowservants, and to eat and drink with the drunken; The lord of that servant shall come in a day when he looketh not for him, and in an hour that he is not aware of, And shall cut him asunder, and appoint him his portion with the hypocrites: there shall be weeping and gnashing of teeth,” (Matthew 24:42-51)
Those who believe in their Heavenly Father are reconciled to Him and intent on becoming more pleasing and obedient to Him, recognizing that He is the rightful and perfect overseer of our souls.