Matthew 5:20 For I tell you that unless your righteousness surpasses that of the Pharisees and the teachers of the law, you will certainly not enter the kingdom of heaven.
Matthew 6:31-33 So do not worry, saying, ‘What shall we eat?’ or ‘What shall we drink?’ or ‘What shall we wear?’ For the pagans run after all these things, and your heavenly Father knows that you need them. But seek first his kingdom and his righteousness, and all these things will be given to you as well.
Matthew 7:13-14 Enter through the narrow gate. For wide is the gate and broad is the road that leads to destruction, and many enter through it. But small is the gate and narrow the road that leads to life, and only a few find it.
Matthew 11:12 From the days of John the Baptist until now, the kingdom of heaven has been forcefully advancing, and forceful men lay hold of it.
Matthew 19:13-14 Little children were brought to Jesus for him to place his hands on them and pray for them. But the disciples rebuked those who brought them. Jesus said, “Let the little children come to me, and do not hinder them, for the kingdom of heaven belongs to such as these.”
Mark 4:30-32 Again he said, “What shall we say the kingdom of God is like, or what parable shall we use to describe it? It is like a mustard seed, which is the smallest seed you plant in the ground. Yet when planted, it grows and becomes the largest of all garden plants, with such big branches that the birds of the air can perch in its shade.”
Mark 9:35-37 Sitting down, Jesus called the Twelve and said, “If anyone wants to be first, he must be the very last, and the servant of all.” He took a little child and had him stand among them. Taking him in his arms, he said to them, “Whoever welcomes one of these little children in my name welcomes me; and whoever welcomes me does not welcome me but the one who sent me.”
Luke 17:20-21 Once, having been asked by the Pharisees when the kingdom of God would come, Jesus replied, “The kingdom of God does not come with your careful observation, nor will people say, ‘Here it is,’ or ‘There it is,’ because the kingdom of God is within you.”
John 3:3-7 In reply Jesus declared, “I tell you the truth, no one can see the kingdom of God unless he is born again.” “How can a man be born when he is old?” Nicodemus asked. “Surely he cannot enter a second time into his mother's womb to be born!” Jesus answered, “I tell you the truth, no one can enter the kingdom of God unless he is born of water and the Spirit. Flesh gives birth to flesh, but the Spirit gives birth to spirit. You should not be surprised at my saying, ‘You must be born again.’
John 18:36 Jesus said, “My kingdom is not of this world. If it were, my servants would fight to prevent my arrest by the Jews. But now my kingdom is from another place.”