In The Name of Allaah, The Most Merciful, The Bestower of Mercy.

Allaah [The Most High] said:

ادْعُوا رَبَّكُمْ تَضَرُّعًا وَخُفْيَةً ۚ إِنَّهُ لَا يُحِبُّ الْمُعْتَدِينَ

Invoke your Lord with humility and in secret. He likes not the aggressors. [Soorah al-A’raaf Ayah 55]

Imaam As’Sadi (rahimahullaah) said: Ad-Du’aa [Invocation or Supplication] includes Du’aa Al-Mas’alah and Du’aa Al-Ibaadah. [Ref 1]

Du’aa Al-Mas’alah [Supplication, when a request is made]: So supplication is to request one’s needs, and is worship when the servant requests that from his Lord. This is because it involves showing one’s poverty before Allaah, the Most High, and ones need to turn to Him, and one’s certain faith that He is the one having full power, the Most Generous, the one who gives bounteously and is Most Merciful. Seeking ones need from someone else from the creation is permissible if the one to whom the request is made is able to hear and understand it, and has the power to respond to it, like saying, ‘O so and so give me food.’

Du’aa Al-Ibaadah [Invocation through worship]: As for invocation through worship, then it is that the person does an act of worship seeking reward and fearing punishment, and this is not correct unless directed to Allaah alone. To direct this to anyone else besides Allaah is major shirk which takes a person out of the Religion [Ref A], and he falls under the threat in the saying of Allaah, the Most High:

وَقَالَ رَبُّكُمُ ادْعُونِي أَسْتَجِبْ لَكُمْ ۚ إِنَّ الَّذِينَ يَسْتَكْبِرُونَ عَنْ عِبَادَتِي سَيَدْخُلُونَ جَهَنَّمَ دَاخِرِينَ

And your Lord said: “Invoke Me, [i.e. believe in My Oneness (Islamic Monotheism)] (and ask Me for anything) I will respond to your (invocation). Verily! Those who scorn My worship [i.e. do not invoke Me, and do not believe in My Oneness, (Islamic Monotheism)] they will surely enter Hell in humiliation!” [40:60] [Ref 2]

Therefore, Allaah commanded (us) to supplicate to Him with humility- being earnest in [our supplication of] request and devotedly in worship. [خُفْيَةً – secretly]- neither loudly nor overtly due to out of fear of [falling] into Riyaa [show off]; rather [it should be done] secretly [i.e. in a low tone] and out of sincerity to Allaah [The Most High].

[إِنَّهُ لَا يُحِبُّ الْمُعْتَدِينَ – He likes not the aggressors]: Meaning: Those who transgress the limits in every affair. And from transgression is when the servant requests from Allaah [things that are not a source of well-being or righteousness] for him, or he goes into extremes whilst asking [Ref 3] [i.e. going beyond what the sharee’ah legislates in acts of worship, either adding acts or words to the act which are not allowed in the Sharee’ah etc [Ref 4], or he raises his voice [i.e. raises his voice where it is not legislated to raise ones voice – for example in the Qunoot it is allowed to raise ones voice but not in other instances unless there is evidence to do so [Ref 5]. All this is considered to be transgression. [Ref 6]

[Ref 1: An Excerpt from ‘Tayseer Al-Kareem Ar-Rahmaan Fee Tafseer Kalaam Al-Mannaan’. Publisher. Daar Ibn Hazm. 1st Ed 1424AH (Year 2003). slightly paraphrased]

[Ref A: See article for further clarification regarding shirk and excuse of ignorance: http://www.manhaj.com/manhaj/articles/uncnb-takfir-and-the-excuse-of-ignorance-shaykh-abd-al-muhsin-al-abbaad.cfm

[Ref 2: English Translation of Usool Ath-Thalaatha page 96’ by Abu Talhah Daawud Burbank (may Allaah have mercy on him and his wife]

[Ref 3: An Excerpt from ‘Tayseer Al-Kareem Ar-Rahmaan Fee Tafseer Kalaam Al-Mannaan’. Publisher. Daar Ibn Hazm. 1st Ed 1424AH (Year 2003). slightly paraphrased]

[Ref 4: For further details regarding this affair- those who are over-stringent or go beyond bounds in acts of worship-, refer to the statements of the scholars in Sharh Saheeh Muslim 16/220 by Imaam An-Nawawi (rahimahullaah); Sharh Riyaadus Saaliheen 1/416-418’ by Shaikh Uthaymeen (rahimahullaah) and Majmoo Al-Fataawaa 10/620 by Shaikhul Islaam Ibn Taymiyyah (rahimahullaah) regarding the innovations of the monks and the innovators]

[Ref 5: Shaikh Bin Baaz (rahimahullaah sheds light on this affair, see link: http://www.binbaz.org.sa/noor/635 ]

[Ref 6: An Excerpt from ‘Tayseer Al-Kareem Ar-Rahmaan Fee Tafseer Kalaam Al-Mannaan’. Publisher. Daar Ibn Hazm. 1st Ed 1424AH (Year 2003). slightly paraphrased]