Lots of persons long to reach his door and remain hopeful about it. But it was predestined for Mumal to reach it and then return home. Verily their life is a frustration (i.e. they achieve nothing in this world), those, whose claims or credentials are malafide, (i.e. whose beliefs are inconsistent with Islam).
And if they had worshipped aught beside Him, surely all their actions would have been of no avail to them. (88, Al-Anam).
Note: There is a possible reference to the ascention of the Prophet and his meeting with Allah and to his safe return home. Other seekers had longed to see Allah but in vain.

Many long to reach his door, it was Moomal who was destined،
To reach there and come back.
The life of those is absurd who have come on a false invitation.