John Gill Reformed Baptist @doctorgill

And all things whatsoever,.... Not only miracles, but any other thing which may be for the honour of God, the interest of religion, the spreading of the Gospel, the enlargement of the kingdom, of Christ, their own spiritual good, and the welfare of immortal souls, ye shall ask in prayer, believing.

Albert Barnes Presbyterian @notesbybarnes

Verse 22. And all things, etc. He adds an encouragement for them to pray, assuring them that they should have all things which they asked. This promise was evidently a special one, given to them in regard to working miracles. To them it was true. But it is manifest that we have no right to apply this promise to ourselves.