But let him ask in faith. He shews here, first the right way of praying; for as we cannot pray without the word, as it were, leading the way, so we must believe before we pray; for we testify by prayer, that we hope to obtain from God the grace which he has promised. Thus every one who has no faith in the promises, prays dissemblingly. Hence, also, we learn what is true faith; for James, after having bidden us to ask in faith, adds this explanation, nothing wavering, or, doubting nothing. Then faith is that which relies on God's promises, and makes us sure of obtaining what we ask. It hence follows, that it is connected with confidence and certainty as to God's love towards us. The verb diakrinesthai, which he uses, means properly to inquire into both sides of a question, after the manner of pleaders. He would have us then to be so convinced of what God has once promised, as not to admit a doubt whether he shall be heard or not. He that wavereth, or doubteth. By this similitude he strikingly expresses how God punishes the unbelief of those who doubt his promises; for, by their own restlessness, they torment themselves inwardly; for there is never any calmness for our souls, except they recumb on the truth of God. He, at length, concludes, that such are unworthy to receive anything from God. This is a remarkable passage, fitted to disprove that impious dogma which is counted as an oracle under the whole Papacy, that is, that we ought to pray doubtingly, and with uncertainty as to our success. This principle, then, we hold, that our prayers are not heard by the Lord, except when we have a confidence that we shall obtain. It cannot indeed be otherwise, but that through the infirmity of our flesh we must be tossed by various temptations, which are like engines employed to shake our confidence; so that no one is found who does not vacillate and tremble according to the feeling of his flesh; but temptations of this kind are at length to be overcome by faith. The case is the same as with a tree, which has struck firm roots; it shakes, indeed, through the blowing of the wind, but is not rooted up; on the contrary, it remains firm in its own place.

But let him ask in faith - See the passages referred to in James 1:5. Compare the Matthew 7:7 note, and Hebrews 11:6 note. We cannot hope to obtain any favor from God if there is not faith; and where, as in regard to the wisdom necessary to guide us, we are sure that it is in accordance with his will to grant it to us, we may come to him with the utmost confidence, the most entire assurance, that it will be granted. In this case, we should come to God without a doubt that, if we ask with a proper spirit, the very thing that we ask will be bestowed on us. We cannot in all other cases be so sure that what we ask will be for our good, or that it will be in accordance with his will to bestow it; and hence, we cannot in such cases come with the same kind of faith. We can then only come with unwavering confidence in God, that he will do what is right and best; and that if he sees that what we ask will be for our good, he will bestow it upon us. Here, however, nothing prevents our coming with the assurance that the very thing which we ask will be conferred on us.
Nothing wavering - (μηδὲν διακρινόμενος mēden diakrinomenos.) "Doubting or hesitating as to nothing, or in no respect." See Acts 20:20; Acts 11:12. In regard to the matter under consideration, there is to be no hesitancy, no doubting, no vacillation of the mind. We are to come to God with the utmost confidence and assurance.
For he that wavereth, is like a wave of the sea - The propriety and beauty of this comparison will be seen at once. The wave of the sea has no stability. It is at the mercy of every wind, and seems to be driven and tossed every way. So he that comes to God with unsettled convictions and hopes, is liable to be driven about by every new feeling that may spring up in the mind. At one moment, hope and faith impel him to come to God; then the mind is at once filled with uncertainty and doubt, and the soul is agitated and restless as the ocean. Compare Isaiah 57:20. Hope on the one hand, and the fear of not obtaining the favor which is desired on the other, keep the mind restless and discomposed.

Let him ask in faith - Believing that God IS; that he has all good; and that he is ever ready to impart to his creatures whatever they need.
Nothing wavering - Μηδεν διακρινομενος· Not judging otherwise; having no doubt concerning the truth of these grand and fundamental principles, never supposing that God will permit him to ask in vain, when he asks sincerely and fervently. Let him not hesitate, let him not be irresolute; no man can believe too much good of God.
Is like a wave of the sea - The man who is not thoroughly persuaded that if he ask of God he shall receive, resembles a wave of the sea; he is in a state of continual agitation; driven by the wind, and tossed: now rising by hope, then sinking by despair.

But let him ask in faith, (f) nothing wavering. (6) For he that wavereth is like a wave of the sea driven with the wind and tossed.
(f) Why then, what need is there of another mediator or priest? (6) A digression or going aside from his matter, as compared to prayers which are conceived with a doubting mind, but we have a trustworthy promise from God, and this is the second part of the epistle.

But let him ask in faith,.... Not only in the faith of the divine Being that God is; but in the faith of the promises he has made; and in the faith of his power and faithfulness to perform them; and in the faith of this, that whatever is asked, according to the will of God, and is for his glory, and his people's good, shall be given.
Nothing wavering; about the thing asked for, whether it is right or no to ask for it; for that should be settled before it is asked for; nor about the power of God to do it; nor about his will, in things he has declared he will do; nor about his faithfulness to his promises; nor at all questioning but what is proper, suitable, and convenient, will be given in God's own time and way.
For he that wavereth is like a wave of the sea driven with the wind and tossed; he is troubled, restless, unquiet, and impatient; and he is fickle, inconstant, unstable, and unsettled; and is easily carried away with every wind of doctrine, temptation, and lust.

ask in faith--that is, the persuasion that God can and will give. James begins and ends with faith. In the middle of the Epistle he removes the hindrances to faith and shows its true character [BENGEL].
wavering--between belief and unbelief. Compare the case of the Israelites, who seemed to partly believe in God's power, but leaned more to unbelief by "limiting" it. On the other hand, compare Acts 10:20; Romans 4:20 ("staggered not . . . through unbelief," literally, as here, "wavered not"); 1-Timothy 2:8.
like a wave of the sea-- Isaiah 57:20; Ephesians 4:14, where the same Greek word occurs for "tossed to and fro," as is here translated, "driven with the wind."
driven with the wind--from without.
tossed--from within, by its own instability [BENGEL]. At one time cast on the shore of faith and hope, at another rolled back into the abyss of unbelief; at one time raised to the height of worldly pride, at another tossed in the sands of despair and affliction [WIESINGER].

But let him ask in faith - A firm confidence in God. St. James also both begins and ends with faith, James 5:15; the hinderances of which he removes in the middle part of his epistle. He that doubteth is like a wave of the sea - Yea, such are all who have not asked and obtained wisdom. Driven with the wind - From without. And tossed - From within, by his own unstableness.