It’s not always the case that the devil hears you when you pray. If you suspect he does, pray in the spirit.
However, Satan is not omniscient, omnipotent, omnipresent like God. It’s pointless sometimes to bind, rebuke, resist or cast him out if he hasn’t manifested. He’ll not be there, and won’t even hear what you say. Luke 4:13 says, “And when the devil had ended all the temptation, he departed from him for a season.”
Next time he reappears, you’ll still know if somehow and in some kind he does, and that he’ll do for sure. Whenever or wherever Christians gather he is likely to show up in some form, so stay vigilant. You’ll know he’s around because the devil is an attention seeker, he won’t go until he’s sent away, whether it’s him personally, his demons, devils, evil spirits, fallen Angels or agents of his, it doesn’t matter. He is such a nuisance, and a very disruptive force in our feasts of charity. However, one good thing about the devil is he obeys and trembles at the command of the word of God, probably he does much better than we all do. James said, “Thou believest that there is one God; thou doest well: the devils also believe, and tremble” (James 2:19). He obeys, you say go in Jesus’ name, and off he goes. It’s not a struggle – “And they overcame him by the blood of the Lamb, and by the word of their testimony…” Revelation 12:11. You’re the stronger man mentioned in Luke 11 – ”But if I with the finger of God cast out devils, no doubt the kingdom of God is come upon you.” Luke 11:20
Anyway, Job 1:6-7 says, “Now there was a day when the sons of God came to present themselves before the Lord, and Satan came also among them. And the Lord said unto Satan, Whence comest thou? Then Satan answered the Lord, and said, From going to and fro in the earth, and from walking up and down in it.” My point here is, when Satan appears don’t ignore him, and don’t carry on as if nothing has happened. If its a service, stop it, and cast him first. He appeared before God along with the sons of God, and God could not wait to send him off. Casting out devils shouldn’t be left to end of the service – you don’t want uninvited guests whose intentions is to steal, kill and destroy.
In the parable of the wedding feast, Jesus said the king said to him, “Friend, how camest thou in hither not having a wedding garment? And he was speechless. Then said the king to the servants, Bind him hand and foot, and take him away, and cast him into outer darkness; there shall be weeping and gnashing of teeth.” Matthew 22:12-13
Apostle Paul said,
“For the mystery of iniquity doth already work: only he who now letteth will let, until he be taken out of the way. And then shall that Wicked be revealed, whom the Lord shall consume with the spirit of his mouth, and shall destroy with the brightness of his coming: Even him, whose coming is after the working of Satan with all power and signs and lying wonders, And with all deceivableness of unrighteousness in them that perish; because they received not the love of the truth, that they might be saved.” 2 Thessalonians 2:7-10
The mystery of iniquity doth already work; his intention is trick everyone.
Read also Fallen Angels