Whether big or small, any miracle is equally easy for God. Just because your petition is “big” or “difficult” doesn’t mean it is any harder for God. Since he is all powerful, nothing is beyond His capabilities.
The reason why “small” miracles seem “easier” is a matter of us — not God. WE believe because it is small. We DON’T believe because it is “big.” But the size of the miracle is irrelevant to Supreme Power.
Therefore I tell you, WHATEVER you ask for in prayer, believe that you have received it, and it will be yours — Mark 11:24 NIV (caps mine). Not every saying of Jesus appears in all the Gospels, but this one features throughout — and it even gets repeated in some of the Gospels. It’s as if God really wanted to underline the truth that WHATEVER or ANYTHING is possible for Him.
So today, pray and believe.