In the case of the man that his child is always involved with the spirit of that deny him of talking the spirit of convulsion. Here is another version of the case, where Jesus was talking to His disciples concerning the use of their faith.
"19 Then came the disciples to Jesus apart, and said, Why could not we cast him out?
20 And Jesus said to them, Because of your unbelief: for truly I say to you, If you have faith as a grain of mustard seed, you shall say to this mountain, Remove hence to yonder place; and it shall remove; and nothing shall be impossible to you.
21 However, this kind goes not out but by prayer and fasting." Matthew 17:19-20 (AKJV)
Our faith has his part to play in our connectivity with the supernatural. Faith is said to be "Now faith is confidence in what we hope for and assurance about what we do not see." Hebrews 11:1 (NIV). The disciples then could not do the work of faith and probably because they think with themselves that certain people with very big anointing will express such faith. Then Jesus told them that it is either you have faith or not, the magnitude of you faith doesn't have to be large as the length of the sea but if it is as small as the mustard seed which seems to be the least in size of the all seed in Israel then: you will instructively move the mountain to precise place. Amen.
Jesus seeing that their connection is not regular with the God divine to explore such faith, He gave an alternative which He call prayer and fasting. Folks let your connection with God be regular even if you will fast and pray for particular reason it won't be always and there will be a quicker response to your prayers.
Our acceptable fasting is getting closer to the author and finisher of our faith and believing so much in the inbuilt confidence in God and be assured that whenever we fast and pray He answer us. Amen.
Do you know some of us still doubt our fasting and prayer by condemning ourselves with unbelief? Don't be like such people their prayers and fasting are result from anxiety and basic worries of their life. Apostle Paul taught us concerning that by hugging us to rather pray on all things with thanksgiving and not worrying about anything. "Never worry about anything. Instead, in every situation let your petitions be made known to God through prayers and requests, with thanksgiving. Philippians 4:6 (ISV)
I pray your worries shall be converted to joy and thanksgiving in Jesus name. Keep focus on the Lord Jesus and when you pray your prayer shall not be delayed. Amen. All you have assumed impossible due to your failing faith shall be made possible in your live in Jesus name. Your celebration and expectations concerning your fasting and prayer shall be done and manifest to the glory of God in Jesus name. Amen.
Prophet Johnson Oluwagbenga Adeniyi