That means the Paradise is a grant (gift) and an account. But Allah (swt) says:

 ﴾وَأَن لَّيْسَ لِلْإِنسَانِ إِلَّا مَا سَعَىٰ % وَأَنَّ سَعْيَهُ سَوْفَ يُرَىٰ % ثُمَّ يُجْزَاهُ الْجَزَاءَ الْأَوْفَىٰ ﴿

(And that there is not for man except that [good] for which he strives

% And that his effort is going to be seen – % Then he will be recompensed for it with the fullest recompense.) (An-Najm: 39-41)

Rasulullah (saws) has said:

(“Verily, none of you will enter Paradise because of his deeds alone.” They said, “Not even you, O Messenger of Allah?” The Prophet said, “Not even me, unless Allah grants me mercy from himself.”)[1]

Allah (swt) mercy is a grant added to justice, the justice is for deeds and the grant is a mercy from Him (swt). Hence, the man enters Paradise due to the mercy of Allah (swt) and not through his own deeds. However, we need to be aware that performing deeds are a condition of entering Paradise.

[1] Musnad Ahmad ibn Hanbal, Hsdith No. 7473.