Question 56: What is the correct and false Tawassul ?
The Answer: At-Tawassul is the infinitive of Tawassala, Yatawassal–meaning to take a means that will make the person reach his intended goal. So, its original meaning is: Seeking to attain the intended objective.
And it is divided into two types:
Correct: And this is the Tawassul through the correct means leading to the intended goal.
Incorrect: And this is the Tawassul by a way that does not lead to the intended objective.
With regard to the first type, and which is the Tawassul by the means that lead to the intended objective, then it is of several types, including:
1-Tawassul (seeking a means of nearness to Allaah) by means of His Attributes, regardless whether it is done in the general or specific sense.
An example on the general way is the statements mentioned in the hadeeth reported by ‘Abdullaah bin Mas’oud (radhi Allaahu anhu) concerning the invocation said to relief from distress and grief:
“O Allaah! I am Your slave, son of Your male slave and female slave. My forelock is in Your Hand. Your judgment concerning me is continuously executed. Your Decree over me is Just. I ask You by every Name which is Yours, with which You Named Yourself, Taught to anyone from Your Creation, or sent down in Your Book, or which You kept to Your Self in the Knowledge of the Hidden with You, that You make the Qur’aan the nurturer (the life of) of my heart, the light of my chest, the removal of my sadness and of my anxiety.” 
This case is a Tawassul by means of Allaah’s Names in the general sense, as in his (صلى الله عليه و سلم) saying: “I ask You by every Name which is Yours, with which You Named Yourself.”
With regard to the specific aspect, then it is to make Tawassul by means of one particular Name for a specific request befitting this Name, like what was reported in the hadeeth of Abu Bakr (radhi Allaahu anhu) when he asked the Prophet (صلى الله عليه و سلم) to inform him of a supplication that he may use in his prayer. So the Prophet (صلى الله عليه و سلم) said:
“Say: O Allaah, I have done great injustice to myself, and none can forgive sin except You, so forgive me a forgiveness from You, and be merciful to me, as You are The Most Forgiving, The Most Merciful” 
So he sought Forgiveness and Mercy and made Tawasssul to Allaah, The Most High, by means of two of His Names befitting what is being requested. So he said: “You are The Most-Forgiving, The Most-Merciful.” This type of Tawassul falls under the Saying of The Most High:
“And (all) the Most Beautiful Names belong to Allaah, so call on Him by them”. [Qur’aan, soorat al-A’raaf (7): 180].
Supplication here comprises two types: Supplication when a request is made (du’aaul mas’alah), and invocation through worship (du’aaul ‘Ibaadah).
With regards to the Tawassul to Allaah by means of His Attributes, then it is like the Tawssul by means of His Names in the sense that it could be general and specific. As to the general way, then it is like your saying: “O Allaah, I ask you by Your Beautiful Names and Most Supreme Attributes,” then you mention your request. And with respect to the specific way, then it is to perform Tawassul to Allaah, The Most High, by means of a particular Attribute that is specifically related to a particular request, like that which was mentioned in the hadeeth:
“O Allaah by Your Knowledge of the Hidden and Unseen, and Your Power over the Creation, grant me life for as long as You Know that life is good for me, and grant me death when death is good for me.” 
Here Tawassul to Allaah, The Most High, is by means of the Attributes of ‘Ilm (Knowledge), and Qudrah (Power): “By Your Knowledge of the Hidden and Unseen, and Your Power over the Creation.” …This comprises the one type of Tawassul.
The Second Type: A person seeks means of Nearness to Allaah by means of His belief in Him and in His Messenger.
So, he says: “O Allaah I have believed in You and in Your Messenger, so forgive me, or grant me success and rectitude.” Or that he says: “O Allaah by my faith in You and in Your Messenger I ask you such and such.”
And from this is the Saying of Allaah:
“Verily! In the Creation of the heavens and the earth, and in the alteration of night and day, there are indeed signs for men of understanding. Those who remember Allaah [always, and in prayers] standing, sitting, and lying down”…to His saying: “Our Rabb! Verily, we have heard the call of one (Muhammad صلى الله عليه و سلم) calling to Faith saying: ‘Believe in your Rabb,’ and we have believed. Our Rabb! Forgive us our sins and expiate from us our evil deeds, and make us die [in the state of righteousness] along with the Abraar” [the pious and righteous believers].” [Qur’aan, soorat aal- ‘Imraan (3): 190-191].
So they sought nearness to Allaah by their Eemaan in Him that He Forgive them their sins, expiate from them their evil deeds, and make them die along with the Abraar.
The Third Type is to make Tawassul to Allaah by means of righteous deeds.
And from this is the story of the three people who entered into a cave to sleep in it. They were trapped in the cave when a boulder [rolled down from the mountain] and blocked the entrance of the cave and they could not remove it away. So each one of them sought a means of nearness (Tawassul) to Allaah by means of a righteous deed that he had done. So the first one of them used his kindness to his parents as Tawassul, and the second used as Tawassul his perfect abstention from fornicating [with his uncle’s daughter]. As to the third one, he used as Tawassul his preserving the right of his employee. Each one of them said: “O Allaah if I did that seeking Your Face, then release us from our situation.” So the rock moved. This is Tawassul to Allaah (Azza wa Jal) by means of a righteous deed.
The Fourth Type is to use as Tawassul the conditions of a person, meaning that the supplicant seeks a means of nearness to Allaah by mentioning his circumstances and his state of need. And From this is the saying of Moosaa (alaihis salam):
“O My Rabb! I am in need of whatever good that You bestow on me.” [Qur’aan, soorat al-Qasas (28): 24].
In doing so, he is using Tawassul to Allaah by mentioning his condition, asking Allaah to bestow whatever good on him. A related case is in the saying of Zakhariyyaah (alaihis salam):
“My Rabb! My bones have grown feeble, and grey hair has spread on my head.” [Qur’aan, soorat Maryam (19): 4].
So these are some of the types of Tawassul, and all of them are allowed since they are good means to use as Tawassul to attain what is being intended.
A Fifth Kind of Tawassul
Question 57: Are there any other types of Tawassul in addition to the four that you have mentioned?
The Answer: Yes, there is an additional type of Tawassul and it is the seeking of nearness to Allaah by means of the supplication of a righteous man and whom it is hoped that his invocation will be answered, because the companions (radhi Allaahu anhum) used to ask the Prophet (صلى الله عليه و سلم) to invoke Allaah for them, generally and specifically.
Indeed it is reported in the saheehayen (al-Bukhaaree and Muslim collections of hadeeth) from the transmission of Anas bin Maalik ((radhi Allaahu anhu)) that a man entered the Mosque on the day of Jumu’ah and the Prophet (صلى الله عليه و سلم) was giving the Khutbah and said: “O Messenger of Allaah, the livestock are dying and the roads are cut off so supplicate to Allaah for us that He should give us rain.” So the Prophet (صلى الله عليه و سلم) raised up his hands and supplicated and said: ‘O Allaah bless us with rain,’-three times…and he did not descend from the minbar (pulpit) until the rain was dripping from his beard. The rain continued for a whole week. And on the next day of Juma’ah the same man or someone else came while the Prophet (صلى الله عليه و سلم) was standing giving Khutbah…and said: ‘Buildings are being destroyed and livestock are being drowned, so supplicate to Allaah to withhold it for us.’ So the Prophet (صلى الله عليه و سلم) raised his hands and said: ‘O Allaah, around us and not upon us…’ so he did not point with his hands in any direction except that the clouds cleared away…and we went out walking in sunshine.” 
And there are several incidences on which the companions asked the Prophet (صلى الله عليه و سلم) to supplicate to Allaah specifically for them. And from this is the case when the Prophet (صلى الله عليه و سلم) mentioned that seventy thousand of his Ummah shall enter Paradise without reckoning nor punishment, and that they are those who do not treat themselves with Ruqya, nor do they believe in good or bad omen nor do they get themselves branded (cauterized), but the put their trust in Allaah; thereupon ‘Ukaashah bin Muhsin stood up and said: “O Messenger of Allaah, supplicate to Allaah to make me from amongst them.” So he (صلى الله عليه و سلم) said: “You are one of them.” 
This is also from the kind of permissible Tawassul: that a person asks someone to supplicate to Allaah, The Most High, for him, if it is hoped for that this person’s supplication will be answered. However, it should be that the person requesting someone to supplicate Allaah for him intends to benefit himself and his brother, the one from whom he asked the supplication, so that the request is not solely for his own interest. Since if you want to benefit your friend as well as yourself, then this will end up as something good for him. This is because when a man supplicates to Allaah for his brother in his absence, the angel says: “Aameen, and for you the same.” Similarly when someone supplicates Allaah for his brother, then he is from those who do good by virtue of this supplication, and Allaah loves those who do good.”
 Reported by Ahmad (1/391) and the wording is his, and al-Haakim (1/509) and others and its isnaad is saheeh as in as-Saheehah (no.199).
 Reported by al-Bukhaaree and Muslim. See Saheeh al-Bukhaaree, vol.8, no.338.
 Reported by al-Bukhaaree and Muslim. See Saheeh al-Bukhaaree, vol.7, no.575.
 Reported by al-Bukhaaree and Muslim. See Saheeh al-Bukhaaree, vol.2, no.55, nos.126-132, no.34, vol.4, no.782, and vol.8, no.115.
 Ruqya: Recitation of Qur’anic texts on an ill or charmed person as a treatment from disease.
Source: Fiqhul ‘Ibaadaat – Understanding Worship, By Sh. Muhammad bin Saalih Al-‘Uthaimeen (rahimahullah), Translated by Saleh as Saleh (rahimahullaah)