I was wondering if it is only the Shaitan and the Jinn that can whisper to mankind. Is it in the Sunnah that angels might whisper to ordinary people for help or guidance? Please give evidence.

Praise be to Allah, the Lord of the Worlds; and may His blessings and peace be upon our Prophet Muhammad and upon all his Family and Companions. Allah The Almighty informed us in His Noble Book that whisper comes form both jinn and mankind: {Who whispereth in the hearts of mankind, of the jinn and of mankind.}[114:5-6]. So, human devils whisper just in the same way the devils of the jinn do. Al-Hasan al-Basri , may Allah have mercy on him, said: The devils of the jinn whisper in the hearts of mankind directly, whereas those of mankind declare their "whisper" publicly. As to the question whether the angels whisper or inspire ordinary human beings, etc., there are two categories of inspirations: That which means audible inspiration from Allah Almighty. This is limited to prophets and messengers (may peace be upon them all). Allah says: {Lo! We inspired thee as We had inspired Noah and the prophets after him…}[4:163]. Yet, an angel might address partially some of the believers. Ibn Al-Qayyim (may Allah have mercy on him) said in his "Madarij As-Salikeen 1/460): This (inspiration, whisper) may take place with people other than prophets. Angels used to say Salaam to (salute) Imran Ibn Hussain , but when he practiced cauterization they no more saluted him. Yet, after he left cauterization they resumed their conversation with him. This inspiration is, in turn, of two kinds: First, dialogue that can be heard by the ear, which is very rare for the ordinary believers. Second, whisper that is thrown to the believer's heart by which the angel addresses his soul, as in the well-known Hadith (Prophet's saying): Verily the angel has (his share of) effect in the son of Adam's heart, as the devil has his share in it…etc. He also mentioned some examples. This second kind of inspiration constitutes the second category, as in Allah's Saying: {And thy Lord inspired the bee...}[16:68]. The first meaning mentioned by Ibn Al-Qayyim is evidenced by the Prophet's Hadith: There were before you among the Children of Israel some inspired men without being prophets. If there is anyone like them among my Ummah (nation), he will be Umar (Ibnul-Khattab). [Narrated by Al-Bukhari from Abu Hurairah (may Allah's Mercy be upon him)] Allah knows best.