Luke 13:24 - The Narrow or Wide Gate?

Strive to enter in at the strait gate: Luke 13:24a (KJV)

Strive. Gr. agonizomai, originally referred to the effort put
forth by a contestant in an athletic contest to qualify for the prize,
and hence came to mean in a general sense "to struggle," or "to
exert oneself." Agonizomai is sometimes used in the NT of the
Christian's efforts to qualify for entrance into the kingdom of heaven (1
Cor. 9:25; Col. 1:29). It is also translated "fight" in 1 Tim. 6:12,
with reference to fighting the good fight of faith (see 2 Tim. 4:7).
[SDA Commentary]

The word translated "strive" is employed in 22:44 to describe
Jesus' struggle in Gethsemane. [Jamieson, Fausset, And Brown
Commentary]

The narrow door is Christ Himself apart from whom there is no
other way to heaven. [Ryrie SB]

Receiving salvation requires more concentrated effort than most
people are willing to put forth. Obviously we cannot save ourselves -
there is no way we can work ourselves into God's favor. The effort we
must put out "to enter through the narrow door" is earnestly desiring
to know Jesus and diligently striving to follow him whatever the
cost. [Life Application SB]

There will be surprises in the kingdom of God. Those who are
very prominent in this world may have to be very humble in the next;
those whom no one notices here may be the princes of the world to
come. There is a story of a woman who had been used to every luxury
and to all respect. She died, and when she arrived in heaven, an
angel was sent to conduct her to her house. They passed many a lovely
mansion and the woman thought that each one, as they came to it, must be
the one allotted to her. When they had passed through the main
streets they came to the outskirts where the houses were much smaller;
and on the very fringe they came to a house which was little more
than a hut. "That is your house," said the conducting angel. "What,"
said the woman, "that! I cannot live in that."  "I am sorry," said
the angel, "but that is all we could build for you with the
materials you sent up." [Barclay Commentary]