Overall meaning : Remember, Muhammad, when Satan made the evil deeds of the Quraysh unbelievers seem fair to them and said to them, 'No one will be able to defeat you today, and I will be close at hand to help you.’ But when the two armies, the Muslims and the unbelievers, came within sight of each other, he turned tail and fled, saying to the Quraysh idolaters, 'I have nothing to do with you. I can see the angels coming down to support the Muslims while you cannot see them. I fear Allah will hasten my punishment in this life and I will perish along with you. Allah is severe in retribution.’
Also remember, Muhammad, when the hypocrites and those who have doubts in their hearts then said, 'Muslims have been so deluded by their religion that they have dared to fight against the Quraysh who are far mightier and larger in number!’ But whoever puts his trust in Allah will find that Allah will surely protect and support him, for Allah is All-Mighty, All-Wise.