The promises do not refer to prayers offered up one for another only, though this is a large part of the cases put forward in Scripture—"pray one for another"; "for me also"; "laboring earnestly for you in prayers"; and many others. But the prayer of faith is not confined to this. There are prayers for opening the door for the gospel, and for all men. We are told in all things to present our requests to God; but then the answer is, or may be only, that "The peace of God, which passeth all understanding, shall keep your hearts and minds through Christ Jesus."
For the prayer of faith, or the promise to it, there are certain limits as to the certainty of answer, such as "in My name," "according to His will," "If ye abide in Me, and My words abide in you, ye shall ask what ye will"; "If two of you agree"; besides what stops prayer, as "a sin unto death." But then I see no limits put to the expectation of faith, if God gives it. If it be my will, asking amiss to consume it on my lusts, I cannot expect an answer. But the Lord contemplates the giving of faith, and certainty of answer for drying up of the fig tree or removing a mountain; and whatever I can ask believing, I receive it. This is a very important principle. But first, the limits on which formal promise of answer rests, besides special faith.
The first passage I may refer to is, "If we ask anything according to His will, He heareth us... and... we know that we have the petitions." This supposes the demand according to His will, and then we can reckon on His power accomplishing it. This is the general Christian confidence, a great boon to be assured of the acting of Him who is almighty in the way of His will.
Next it is said, "If ye abide in Me, and My words abide in you, ye shall ask what ye will." Here I do not doubt there was special reference to the twelve, but in principle it applies to all Christians. Where the mind is formed by the words of Christ, when they abide in one who lives in dependence on and confidence in Him—one thus abiding in Him, having Him in spirit, and his mind guided by Christ's word, his will is (so to speak) Christ's—he asks what he will, and it will come.
Another case is where any two are agreed; here individual will is set aside. It is where Christians have a common desire, and agree to present it to God. The deliberate formal agreement supposes a common Christian mind, and it will be done. So when I ask, coming for what I can attach Christ's name to, under His authority, the Father will do it. Here, I doubt not too, the twelve are specially in view; still it is in principle every Christian.
A man cannot in faith bring Christ's name attached to his lusts; and all these statements suppose the disciple and faith, as James expressly teaches us, and indeed the Lord Himself. But there are other statements which cast us more generally on the goodness of God and His interest in us, and show us that where faith is in exercise, the answer will be there. "All things, whatsoever ye shall ask in prayer, believing, ye shall receive." This supposes faith, and intimacy, so to speak, with God. The heart is supposed to be in His interests, and then if there is faith as a grain of mustard seed, a mountain goes.
I do not doubt this kind of faith was much more when any, as the apostles, felt themselves interested in God's cause, identified with Him and it on the earth; but there is no limit to it. Where such faith is, such answer will be; and God is as much occupied now with the details of blessing for us, as for the great deeds of those days.
Not a sparrow falls now without Him any more than then; and the effectual fervent prayer of a righteous man availing much is ever true; only one must, so to speak, put ourselves with God, for those to whom these things were said were identified with Him in His interests on the earth. This gave their prayers of course a peculiar place; but then if faith (that is, the operation of His Spirit and grace) brings me into His interests now even in details, the promise is there, and we can reckon on God and His power exercised in love now as then. There is no limit; only it is the working of His Spirit in us, and hence faith that reckons on the answer.
Presenting our requests, subject to His will, is always right; of this we can have an example even in Gethsemane; so Paul for his thorn in the flesh. And the answer will be more glorious and blessed than the request, even when it does not answer it as we may have anticipated. See John 12 and Psalm 32. So Psalm 21, and even Paul's request about the thorn.
Let us trust His love, and this will not come short; and if He has given us faith to expect a specific answer, bless God for it. Only our will must not come in, even if it were answered (this was the case of the quails), but as a rule not, as James teaches. But where there is earnest faith, God will surely hear, though He may give us safeguards against our own will in it.