I don't base my faith on miracles, but there are plenty of examples out there it you search for them online.
For example Bono (the U2 guy) grew up in Ireland in the late 70s, in a time when heroin was taking hold of youth culture in Dublin. Bono along with Edge and Larry, were part of the shalom house church movement. They would pray for people to break off their addiction to heroin, and people would be freed from heroin addiction instantly, which if you know about heroin addiction is a powerful thing. The band left this movement in the early 80s, but they still have their faith (recorded in the books U2 by U2 and the steve stockman book).
The whole thing with sacrificing his son makes sense when we consider the human condition as the bible describes it, that
1) humans were created to be in a relationship with God.
2) however since Adam blotted his copybook, the problem of "sin" occured, and human beings have a problem with sin, that is we basically choose to go our own way rather than go God's way
3) Because of the nature of God who is holy (that is perfect), we are condemed to die. In order to relate to God somebody needed to pay the price for our sin, so that's where Jesus dying on the cross for us comes in.
4) We can be forgiven by asking God to forgive us via what Jesus did. Therefore now we can stand before God forgiven if we do this