The Lord will keep you from all harm - he will watch over your life; the Lord will watch over your coming and going both now and forevermore. (Psalm 121:7, 8)
Is God able to fulfill the things that you read in the above verses? Yes, he is! And he does it countless times in the lives of believers. Doesn't mean that believers don't fall sick or get injured. But the restraining hand of God prevents what would have been catastrophic.
Jabez prayed to God,
"Oh, that you would bless me and enlarge my territory! Let your hand be with me, and keep me from harm so that I will be free from pain." And God granted his request.(1 Chronicles 4:10)(NIV)
...keep me from harm so that I will be free from pain....That's a neat little prayer we can pray each day. In the KJV, it's a bit different. There we read....keep me from evil, that it may not grieve me.
The thing to notice here is that God granted his request.
We all need divine protection, what with the devil prowling around like a roaring lion seeking to devour. But God's promises stand us in good stead if we pray them.
I will remain in the world no longer, but they are still in the world, and I am coming to you. Holy Father, protect them by the power of your name--the name you gave me--so that they may be one as we are one. (John 17:11)
My prayer is not that you take them out of the world but that you protect them from the evil one. (John 17:15)
Yes, God will protect you and your family from all calamities if you live a life pleasing to him. Sin opens the way for satanic attacks, so we must strive to walk with God, obeying his Word. Then his promises will be fulfilled every day of our lives.
The Apostle Paul affirms,
The Lord is faithful, and he will strengthen and protect you from the evil one.
(2 Thessalonians 3:3)