Some people in my country recite the following supplications which have no Islamic basis. Some of are innovated and contain statements of Shirk (associating others in worship with Allah). Moreover, they attribute these supplications to the Commander of the Believers `Ali Ibn Abu Talib (May Allah be pleased with him) and others. They recite these supplications in the sessions of remembering Allah or in Masjids (mosques) after Al­Maghrib (sunset) Prayer claiming that they draw them near to Allah. For example, they say: "By the right of Allah, O men of Allah, provide us with the aid of Allah and be the help sent to us from Allah." They also say: "O Aqtab (poles), O Awtad (pillars), O masters, respond. O supporters, intercede to Allah on behalf of this servant who stands at your door, because he is afraid of his negligence. O Messenger of Allah, relieve us! You are my only resort and you are the only one to ask. You (people we call) are the best of the pious because of Hamzah, the master of martyrs, and from whom else could we seek help?! Help, O Messenger of Allah." They say: "O Allah, invoke peace and blessings on the one whom You made reason for revealing Your Mighty Secrets and the eminence of Your Merciful Light, who is the deputy of the Divine Presence and the vicegerent of Your Divine Secrets."

Could you please explain what is Bid`ah (innovation in Islam) and what is Shirk? Is offering Salah behind an Imam who repeats such supplication valid?