Who are those who do not wear robes at the heavenly feast? These are people who went to church but do not truly believe in Jesus as the Christ. (Mt 22:10-13, Gal 3:26-27, Rom 13:14)
Mt 22:10 So those servants went out into the highways, and gathered together all as many as they found, both bad and good: and the wedding was furnished with guests.
11 And when the king came in to see the guests, he saw there a man which had not on a wedding garment:
12 And he saith unto him, Friend, how camest thou in hither not having a wedding garment? And he was speechless.
13 Then said the king to the servants, Bind him hand and foot, and take him away, and cast him into outer darkness, there shall be weeping and gnashing of teeth.
Gal 3:26 For ye are all the children of God by faith in Christ Jesus.
27 For as many of you as have been baptized into Christ have put on Christ.
Rom 13:14 But put ye on the Lord Jesus Christ, and make not provision for the flesh, to fulfil the lusts thereof.