Praise be to Allah.
It is not permissible to seek intercession in this world from one who is dead or absent, even if it is proven that he will be an intercessor in the hereafter. Therefore it is not permissible to say: “O Messenger of Allah, intercede for me” or “O angels of Allah, intercede for me,” even though the angels and the Prophets will intercede on the Day of Resurrection, because asking for intercession can only be done at the appropriate time, when the Prophet is alive and present. At that time the people will come to him and say to him: “Intercede for us with your Lord,” as is mentioned in the famous hadith about intercession.
As for asking for intercession now, that is seeking intercession from one who is absent, and no permission has been given to seek intercession from him. Therefore it is prohibited and comes under the general meaning of the prohibition on asking of and calling upon anyone other than Allah.
Hence there is no report from any of the Sahaabah that they sought intercession from the Prophet (blessings and peace of Allah be upon him) after he died.
As for asking for supplication or intercession from one who is dead, by saying, “Pray to Allah for me” or “Intercede for me with your Lord,” there is a difference of scholarly opinion as to whether it constitutes shirk or is a means that leads to shirk.
As for asking directly of one who is dead, such as saying, “Relieve my distress” or “Meet my need” or “Help me” or “Madad (grant me aid),” this constitutes major shirk according to scholarly consensus.
It is not permissible to say, “O Ramadan, intercede for me,” even though it is proven that fasting will intercede for its people on the Day of Resurrection, because Ramadan is the month, and the month cannot intercede. Moreover, no permission has been granted to address the intercessor and ask of him, and this comes under the heading of asking of something or someone other than Allah, and the basic principle is that that is not allowed.
Dr. Khaalid al-Mushayqih (may Allah preserve him) was asked:
What is the ruling on seeking intercession from anyone or anything other than Allah? I could not figure out the ruling on this text message, “Ramadaan, O generous one, intercede for me with a most merciful Lord…”
He replied: Undoubtedly this is an innovation (bid‘ah). There is nothing wrong with seeking intercession from one who is alive and is able to do it, such as if you were to say, “Intercede for me so that Allah might forgive me,” meaning: Pray for me that Allah might forgive me. There is nothing wrong with this. However, asking someone else to offer supplication (du‘aa’) for one is a matter concerning which there is a difference of opinion among the scholars. But, as Shaykh al-Islam Ibn Taymiyah (may Allah be pleased with him) said: If the intention of the one who makes this request is to benefit from the supplication of the other person, this is permissible and there is nothing wrong with it, if Allah wills.
But if someone asks the dead to intercede for him with Allah, may He be glorified and exalted, this is undoubtedly prohibited and is not permitted.
Some of the scholars regard it as major shirk, and some of them regard it as minor shirk.
Asking Ramadan to intercede is prohibited and is a type of overstepping the mark in supplication, because Ramadan cannot intercede; rather the means of drawing close to Allah that the Muslim should seek in the month of Ramadan is fearing his Lord, may He be glorified and exalted, during that month. This is what brings a person closer to Allah, may He be glorified and exalted, if he obeys His commands and heeds His prohibitions. And Allah is the source of strength.
With regard to the words, “O Ramadan, testify in our favour,” it does not seem that there is any real request in them, but it is better not to say that.
And Allah knows best.