One word which has been encouraging to me for some time is that we have the power with God's help to tie up Satan‘s hands so that he's unable to work as he likes in our life.  I take that promise for my own life from this verse:
Matthew 18:18 "Truly I say to you, whatever you bind on earth shall have been bound in heaven; and whatever you loose on earth shall have been loosed in heaven."
God defeated Satan with the cross, completely taking his power away, but the Lord wants us to join in that work now by working with Him and in union with other disciples to 'bind' Satan's (and all his agents) hands up to where they can't work.  One day the devil will be thrown into the lake of fire forever and even he himself will be tormented (Rev 20:10)! Praise God!  But today he's roaming around and working as much as he can until the time the Lord has set.
So Satan is desiring to cause disaster in in our homes, in our marriages, in our churches, and in our own hearts - but we have the power to bind his works by praying, and by praying in unity.  Husband and wife can bind things in their children’s lives, members in the church can bind things when they pray with one another, etc.  See again in Matthew 18 verse 19,  "Again I say to you, that if two of you agree on earth about anything that they may ask, it shall be done for them by My Father who is in heaven."
So that's binding Satan's hands.  But there’s another verse which is very interesting in Matthew 13:58, and also similarly in Mark 6:5-6 - that says that the Lord was not able to do many works for His own hometown because they had such unbelief:
Matt 13:58 "And He did not do many miracles there because of their unbelief."
Mark 6:6:5-6 "And He could do no miracle there except that He laid His hands on a few sick people and healed them.  And He wondered at their unbelief..."
We say we want to bind Satan's hands, but I believe we read in this verse itself that we by our unbelief may be tying ropes instead around God's hands in our life!  Maybe He’s able to work in many other people's lives the way He wants, but with regard to my own life His hands may be tied if I have unbelief! Wow.
Imagine the Father reaching down from Heaven to (figuratively) lift up a boy and care and comfort and encourage him.  And as the Father is reaching down from Heaven to help this boy, the boy reaches up to His Father's hands... but he doesn't take His loving hands and hold them and receive His loving care; instead the boy places handcuffs on His Dad's wrists, and then takes a rope and wraps up the wrists and hands that were reaching down to lift him up!  I believe this is exactly what we do when we don’t trust our Father, and we don’t believe He can help.  When we focus not on the hope and promises we have in Christ, and His power, but instead on how bad the situation is.
I think one word for this which often sums up unbelief is: "Negativity".  A spirit of negativity is the spiritual equivalent of tying ropes around the hands of the Father who is trying to reach down to pick me up and love me.
I sometimes had to repent of and ask God to forgive me for my ‘sighs’ of negativity.  I don't always use words, but have often let out a ‘sigh’ of unbelief that with my groan was actually in reality saying "Oh great I have to deal with this again."  And when I think about what it implies I have to admit that it is saying that what God has chosen to allow is bad.  It's not for my good (it denies the plain truth of Romans 8:28).  Or at least, with my negativity I'm confessing that the trouble/hassle of the trial is not worth the good that it would bring.
But there's something important about faith: Faith is not just believing that what God says is true, but it's also believing that it's as valuable as He says it is!  It's not only believing His Word, but believing it to the point that we're enthusiastic about it (I believe we see this in the parables of the treasure/pearl of great price Matthew 13:44-45).  And so I've seen I have to repent of negativity.
We have to have a constant attitude of faith that just as the Lord turned the worst thing that ever happened in the universe (the death of Jesus) into the best thing (Jesus dying for us, rising again and saving us forever) - we have to be confident every ‘bad’ thing is not bad, it’s actually good if we love the Lord, and if it's fully submitted to Him so that He can do something with it.  And it's not just 'good', but it's REALLY REALLY good!
A faith filled Christian MUST be an optimistic Christian.  Always hopeful, always patient, exulting in tribulation instead of cursing it.  Romans 5:3-4 "And not only this, but we also exult in our tribulations, knowing that tribulation brings about perseverance; 5:4   and perseverance, proven character; and proven character, hope;"
"Rejoicing in hope, persevering in tribulation" (Rom 12:12),
Be "imitators of those who through faith and patience inherit the promises" (Heb 6:12)
So I see now more of the seriousness with which I need to take unbelief, when I see what it is – unbelief actually is tying up the hands of God so that He cannot work.
Unbelief is not an 'innocent sin', committed by poor unlucky people who deserve pity from a God who has been too hard on them!  It’s tying ropes around the very One who’s loved us from the beginning, and Who wants to help us even more than we want to help ourselves.  But accepting every single situation that comes our way (both good, and difficult) as from His loving hand is what frees Him up to work mightily in our life, and also is the very thing we can do which pleases Him (Heb 11:6).