1 Samuel 1:12
"And it came to pass, as she continued praying before the LORD, that Eli marked her mouth."
Cross References (ranked by relevance)
1 Thessalonians 5:17
Pray without ceasing.
James 5:16
Confess your faults one to another, and pray one for another, that ye may be healed. The effectual fervent prayer of a righteous man availeth much.
Luke 18:1
And he spake a parable unto them to this end, that men ought always to pray, and not to faint;
Ephesians 6:18
Praying always with all prayer and supplication in the Spirit, and watching thereunto with all perseverance and supplication for all saints;
Colossians 4:2
Continue in prayer, and watch in the same with thanksgiving;