Matthew 13:21
but, having no root within him, endureth only for a time; and when tribulation or persecution ariseth on account of the word, he immediately falleth away.
Luke 18:1
And he spoke a parable to them to show that they ought to pray always, and not be fainthearted:
Acts 10:2
a devout man, and one that feared God with all his house, giving much alms to the people, and praying to God always,
Ephesians 6:18
praying with all prayer and entreaty at all times in the Spirit; and watching to this end with all perseverance and entreaty for all the saints,
1 Thessalonians 5:17
Pray without ceasing;