Liar is he who thinks he can enter Paradise other than its door

قَالَ رَسُولُ اللهِ صَلَّي اللهُ عَلَيْهِ وَ آلِهٖ أَنَا مَدِينَةُ الْجَنَّةِ وَ أَنْتَ بَابُهَا يَا عَلِيُّ كَذَبَ مَنْ زَعَمَ أَنَّهُ يَدْخُلُهَا مِنْ غَيْرِ بَابِهَا

The Messenger of Allah (peace be on him and his progeny) warned,

“I am the city of Paradise and you are its gate, O Ali! He has lied who thinks that he will enter it (Paradise) other than its door.”

References:

1.    Al-Amaali of al-Shaikh al-Toosi (r.a.), p. 309, 11^th Majlis

2.    Bashaarah al-Mustafa (peace be on him and his progeny) le Shiah al-Murtaza (peace be on him), p. 208

3.    Behaar al-Anwaar, vol. 40, p. 200, H. 1

Note:

In some narrations, the word wisdom is used instead of Paradise.