Number him, then, O my God, with such as have allowed nothing whatever to deter them from beholding Thy beauty, or from meditating on the wondrous evidences of Thine everlasting handiwork, that he may have fellowship with none except Thee, and turn to naught save Thyself, and discover in whatever hath been created by Thee in the kingdoms of earth and heaven nothing but Thy wondrous Beauty and the revelation of the splendors of Thy face, and be so immersed beneath the billowing oceans of Thine overruling providence and the surging seas of Thy holy unity, that he will forget every mention except the mention of Thy transcendent oneness, and banish from his soul the traces of all evil suggestions, O Thou in Whose hands are the kingdoms of all names and attributes!
(Bahá’u’lláh, Prayers and Meditations by Bahá’u’lláh, CLXXXIV) 
Teach ye your children so that they may peruse the divine verses every morn and eve. God hath prescribed unto every father to educate his children, both boys and girls, in the sciences and in morals, and in crafts and professions.
(Bahá’u’lláh, from a Tablet—translated from the Arabic) 
Worship thou God in such wise that if thy worship lead thee to the fire, no alteration in thine adoration would be produced, and so likewise if thy recompense should be paradise. Thus and thus alone should be the worship which befitteth the one True God. Shouldst thou worship Him because of fear, this would be unseemly in the sanctified Court of His presence, and could not be regarded as an act by thee dedicated to the Oneness of His Being. Or if thy gaze should be on paradise, and thou shouldst worship Him while cherishing such a hope, thou wouldst make God’s creation a partner with Him, notwithstanding the fact that paradise is desired by men.
(The Báb, Selections from the Writings of the Báb, pp. 77–78) 
It is seemly that the servant should, after each prayer, supplicate God to bestow mercy and forgiveness upon his parents. Thereupon God’s call will be raised: “Thousand upon thousand of what thou hast asked for thy parents shall be thy recompense!” Blessed is he who remembereth his parents when communing with God. There is, verily, no God but Him, the Mighty, the Well-Beloved.
(The Báb, Selections from the Writings of the Báb, p. 94) 
O Lord! In this Most Great Dispensation Thou dost accept the intercession of children in behalf of their parents. This is one of the special infinite bestowals of this Dispensation. Therefore, O Thou kind Lord, accept the request of this Thy servant at the threshold of Thy singleness and submerge his father in the ocean of Thy grace, because this son hath arisen to render Thee service and is exerting effort at all times in the pathway of Thy love. Verily, Thou art the Giver, the Forgiver and the Kind!
(‘Abdu’l-Bahá, in Bahá’í Prayers: A Selection of Prayers Revealed by Bahá’u’lláh, the Báb, and ‘Abdu’l-Bahá (Wilmette: Bahá’í Publishing Trust, 2002) p. 63) 
Thou hast asked about material means and prayer. Prayer is like the spirit and material means are like the human hand. The spirit operateth through the instrumentality of the hand. Although the one true God is the All-Provider, it is the earth which is the means to supply sustenance. “The heaven hath sustenance for you”5 but when sustenance is decreed it becometh available, whatever the means may be. When man refuseth to use material means, he is like a thirsty one who seeketh to quench his thirst through means other than water or other liquids. The Almighty Lord is the provider of water, and its maker, and hath decreed that it be used to quench man’s thirst, but its use is dependent upon His Will. If it should not be in conformity with His Will, man is afflicted with a thirst which the oceans cannot quench.
(‘Abdu’l-Bahá, from a Tablet—translated from the Persian) 
With regard to your question as to the value of intuition as a source of guidance for the individual: implicit faith in our intuitive powers is unwise, but through daily prayer and sustained effort one can discover, though not always and fully, God’s will intuitively. Under no circumstances, however, can a person be absolutely certain that he is recognizing God’s will, through the exercise of his intuition. It often happens that the latter results in completely misrepresenting the truth, and thus becomes a source of error rather than of guidance.
(From a letter dated 29 October 1938 written on behalf of Shoghi Effendi to an individual believer) 
… the Guardian feels that it would be better for either the mothers of Bahá’í children, or some Committee your Assembly might delegate the task to, to choose excerpts from the Sacred Words to be used by the child rather than just something made up. Of course prayer can be purely spontaneous, but many of the sentences and thoughts combined in Bahá’í writings of a devotional nature are easy to grasp, and the revealed Word is endowed with a power of its own.
(From a letter dated 8 August 1942 written on behalf of Shoghi Effendi to the National Spiritual Assembly of the British Isles) 
The need is very great, everywhere in the world, in and outside the Faith, for a true spiritual awareness to pervade and motivate people’s lives. No amount of administrative procedure or adherence to rules can take the place of this soul-characteristic, this spirituality which is the essence of man.
(From a letter dated 25 April 1945 written on behalf of Shoghi Effendi to an individual believer) 
... as the Cause embraces members of all races and religions we should be careful not to introduce into it the customs of our previous beliefs. Bahá’u’lláh has given us the obligatory prayers, also prayers before sleeping, for travellers, etc. We should not introduce a new set of prayers He has not specified, when He has given us already so many, for so many occasions.
(From a letter dated 27 September 1947 written on behalf of Shoghi Effendi to an individual believer) 
He suggests that, in addition to your usual teaching work there, you make a special point of praying ardently not only for success in general, but that God may send to you the souls that are ready. There are such souls in every city, but to find them and make the right contact is not easy.
(From a letter dated 18 March 1950 written on behalf of Shoghi Effendi to the Local Spiritual Assembly of Punta Arenas, Chile) 
Regarding your question about prayer and the fact that some of our problems are not solved through prayer, we must always realize that life brings to us many situations, some of which are tests sent from God to train our characters, some of which are accidental because we live in the world of nature and are subject to the accidents of death, disease, etc., and some of which we bring on ourselves by folly, selfishness or some other weak human trait.
It is not correct to say that because a loved one dies, or is not cured of a disease, or a problem is not solved, that God did not answer our prayer, or that we did not pray to Him in a way to receive a favourable answer. Maybe what we prayed for was not the Will of God or was the result of an accident and it produced an irrevocable conclusion like death or disease or bankruptcy etc.
As you say, sometimes the Bahá’ís believe that they are carrying out the Will of God and yet we see that the results are very bad; we must therefore assume that they were deluding themselves into believing that their decision and course of action was according to His Will. What it all amounts to is this, that we should supplicate God, but always with the reservation that we prefer His Will to ours. We should also live up to the Laws of His Teachings, for the more we do this, the more we are exemplary believers, the more sure we will be of receiving a greater degree of His guidance.
(From a letter dated 18 March 1951 written on behalf of Shoghi Effendi to an individual believer) 
The Guardian will pray for the quickening of your souls, the unfolding of the divine mysteries, and the blessings of the Holy Spirit. It is the Holy Spirit that gives new life, and this can today be found in rich abundance, in the Writings of Bahá’u’lláh. His Words and Teachings are the Water of Life, and the sustenance of spiritual growth. Therefore you should study the Word carefully, meditate on its import and, having been touched by its spirit, associate your mind and heart with its atmosphere, then the way will become clear, and the doors be opened.
(From a letter dated 11 June 1956 written on behalf of Shoghi Effendi to a Bahá’í Study Group in Columbus, Ohio)