Two things that lead one to Paradise or Hell
Jabir (radi Allahu anhu) reported: A bedouin came to the Prophet (sal Allahu alaihi wa sallam) and asked him, “O Messenger of Allah, what are the two imperatives which lead to Jannah or Hell”. He (sal Allahu alaihi wa sallam) replied, “He who dies without associating anything with Allah will enter Jannah, and he who dies associating partners with Allah will enter the Fire.”
This Hadith also holds promise for a Muslim that being a Muslim and Muwahhid (believer in the Oneness of Allah) he will be at last sent to Jannah. Whether he goes straight to Jannah or after suffering the punishment of his sins in Hell, is a separate issue, but he will not remain in Hell for ever. Eternal punishment in Hell is reserved only for pagans, polytheists, and infidels.
And Allah Knows Best!