Every Christian, who humbly and sincerely addresses his Maker, may reasonably expect an answer. It does not well appear how a perfectly just and holy Being could impose on his creatures the duty of prayer, without recognizing the obligation of returning an answer of some kind. In making this remark, we imply, of course, that the prayer is a sincere one. An insincere prayer, just so far as insincerity exists, is not entitled to be regarded as prayer, in any proper sense of the term. Our first position, therefore, is, that every person, who utters a sincere prayer, may reasonably expect an answer, and that in fact an answer always is given, although it is not always understood and received. And this appears to be entirely in accordance with the Scriptures. "Ask, and it SHALL be given unto you; seek and ye SHALL find; knock and it SHALL be opened unto you. For every one that asketh RECEIVETH; and he that seeketh FINDETH; and to him, that knocketh, it shall be OPENED."
But it becomes now an important inquiry, What is the true and just answer of God to the petitions of his people? It seems to us that it is, and it cannot be any thing else, than the decision of his own infinitely just and omniscient mind, that he will give to the supplicant or withhold, just as he sees best. In other words the true answer to prayer is God's deliberate purpose or will, existing in connection with the petition and all the circumstances of the petition.
But some will say, perhaps, that on this system we sometimes get our answer, without getting what we ask for; and that God's decision may not correspond with our own desire. But this objection is met by a moment's consideration of the nature of prayer. There never was true prayer, there never can be true prayer, which does not recognize, either expressly or by implication, an entire submission to the divine will. The very idea of prayer implies a right on the part of the person to whom the prayer is addressed, either to give or to withhold the petition. And the existence of such a right on the part of God implies a correlative obligation on the other party to submit cheerfully to his decisions. To ask absolutely, without submission to God's will, is not to pray, but to demand. A demand is as different from true prayer, as a humble request is from an imperative order. A request God always regards; he always treats it with kindness and justice; but a demand cannot be properly addressed to Him, nor can it properly be received by Him.
The true model of the spirit of supplication, even in our greatest necessities, is to be found in the Savior's prayer at the time of his agony in the garden. "And he went a little farther, and fell on his face, and prayed, saying, O my Father, if it be possible, let this cup pass from me; nevertheless, not as I will, but as thou wilt." True prayer, therefore, that prayer, which can be suitably addressed to the Supreme Being, and that which it is suitable for an imperfect and limited mind to offer, always involves the condition, whether it be expressed or not, that the petition is agreeable to the divine will. This condition is absolutely essential to the nature of the prayer. There is no acceptable prayer, there is no true prayer without it. Such being the nature of the prayer, the answer to the prayer will correspond to it, viz., it will always be the decision of the divine mind, whatever that decision may be, made up in view of the petition, and of all the attendant circumstances.
— edited from The Interior or Hidden Life (2nd edition, 1844) Part 3, Chapter 9.