Is it religiously permissible to supplicate to God through an intermediary?
It is religiously permissible to supplicate to God by means of an intermediary such as highly righteous persons. Especially, supplicating God through Prophets and Prophet Muhammad (peace be upon them all) is an inducement for its acceptance. In fact, by the ordinance of the verse, Surely God and His angels bless the Prophet (He always treats him with His special mercy, with the angels praying to Him to grant him the highest station of praise with Him and for the decisive victory of his Religion). O you who believe, invoke the blessings of God on him, and pray to God to bestow His peace on him, greeting him with the best greeting. (Love and follow him with utmost sincerity and faithfulness, and give yourselves to his way with perfect submission.), (1) it is pointed out the importance of the subject.
Furthermore, in a hadith narrated by Anas bin Malik, it is pointed out the importance of sending Salat (supplication) upon Prophet Muhammad (pbuh), Whoever sends a Salat upon me, God sends ten upon him, forgives ten of his sins, and raises his level ten times. (2)
For this reason, it is permissible to request something from God for the sake of those whether it be a Prophet, a righteous person, or a companion (of Prophet Muhammad). However, it is not religiously permissible to make wishes by lighting candles, wrapping ropes and strings in the tombs of saints as it is done at the present days.
It is narrated by Anas (as), during the caliphate of Hazrath Omar (as), whenever there was drought He (as) used to ask Al-Abbas (as) to supplicate God (swt) for rain. He used to say, "O God (swt) we used to ask our prophet to supplicate you for rain, and you would bless us with rain, and now we ask his uncle to supplicate you for rain! Bless us with rain. For a long time, our elders too, used to supplicate as, O God, for the sake of Your lovers and Your beloved ones, we ask You to bestow Your mercy and blessings on us and make our request possible.
(1) Al-Ahzab Surah, 33/56.
(2) Nesâi, Sehiv 55, (3, 50)