Matthew 7:13-14
13 Enter ye in at the strait gate(4439): for wide is the gate, and broad is the way, that leadeth to destruction, and many there be which go in thereat:
14 Because strait is the gate, and narrow is the way, which leadeth unto life, and few there be that find it.
John 10:7-9
7 Then said Jesus unto them again, Verily, verily, I say unto you, I am the door of the sheep.
8 All that ever came before me are thieves and robbers: but the sheep did not hear them.
9 I am the door: by me if any man enter in, he shall be saved, and shall go in and out, and find pasture.
Psalms 118:19-20
19 Open to me the gates of righteousness: I will go into them, and I will praise the LORD:
20 This gate of the LORD, into which the righteous shall enter.