Jesus answers them very succinctly by telling them to believe with Holy Spirit faith.     

Jesus did not come to show off and then leave us in awe.     He came to:
   → clean us up
   → teach us
   → empower us
   → to be like Him.     

Jesus is telling us to operate in the supernatural faith of His Holy Spirit.     

Note: The word 'in' is not in the original Greek phrase which the KJV translates as 'Have faith in God'.     It should have read 'Have God faith' or 'Have the faith of God' rather than 'faith in God'.     

Since we know that God is Spirit (making Him the Holy Spirit of Christ Jesus), this phrase should best be rendered as 'Have Holy Spirit faith'.     

Remember, Faith is one of the Spirit Fruit.     

Unfortunately, this is another example of how the 'God being' was given an existence separate from the Word and Holy Spirit as a result of the translators' trinitarian concept of the Creator.     

Jesus goes on in this passage to tell His disciples to just speak (word) and believe ( Holy Spirit faith) and their desires would be met.     There is no indication that some other being is involved in the process.     

Even, the 'when you pray' statement of Mar 11:24 is misunderstood to reference a 'God being' when Jesus instructed us to pray to our Heavenly Father who is His Holy Spirit.