My children are with me in bed - Or, I and my children are in bed; this is Bishop Pearce's translation, and seems to some preferable to the common one. See a like form of speech in 1 Corinthians 16:11, and in Ephesians 3:18. However, we may conceive that he had his little children, τα παιδια, in bed with him; and this heightened the difficulty of yielding to his neighbor's request.

But if he persevere knocking. (At si ille perseveraverit pulsans). This sentence is added to the beginning of Luke 11:8, by the Armenian, Vulgate, four copies of the Itala, Ambrose, Augustin, and Bede. On these authorities (as I find it in no Greek MS). I cannot insert it as a part of the original text; but it is necessarily implied; for, as Bishop Pearce justly observes, unless the man in the parable be represented as continuing to solicit his friend, he could not possibly be said to use importunity: once only to ask is not to be importunate.

because of.

Luke 18:1-8 And he spoke a parable to them to this end, that men ought always to pray, and not to faint...

Genesis 32:26 And he said, Let me go, for the day breaks. And he said, I will not let you go, except you bless me.

Matthew 15:22-28 And, behold, a woman of Canaan came out of the same coasts, and cried to him, saying, Have mercy on me, O Lord...

Romans 15:30 Now I beseech you, brothers, for the Lord Jesus Christ's sake, and for the love of the Spirit...

2 Corinthians 12:8 For this thing I sought the Lord thrice, that it might depart from me.

Colossians 2:1 For I would that you knew what great conflict I have for you, and for them at Laodicea...

Colossians 4:12 Epaphras, who is one of you, a servant of Christ, salutes you, always laboring fervently for you in prayers...

How to Pray
'And it came to pass, that, as He was praying in a certain place, when He ceased, one of His disciples said unto Him, Lord, teach us to pray, as John also taught His disciples. 2. And He said unto them, When ye pray, say, Our Father which art in heaven, Hallowed be Thy name. Thy kingdom come. Thy will be done, as in heaven, so in earth. 3. Give us day by day our daily bread. 4. And forgive us our sins; for we also forgive every one that is indebted to us. And lead us not into temptation; but deliver …
Alexander Maclaren—Expositions Of Holy Scripture

It Shall not be Forgiven.
And whosoever shall speak a word against the Son of man, it shall be forgiven him: but unto him that blasphemeth against the Holy Ghost, it shall not be forgiven.--LUKE xi. 18. Whatever belonging to the region of thought and feeling is uttered in words, is of necessity uttered imperfectly. For thought and feeling are infinite, and human speech, although far-reaching in scope, and marvellous in delicacy, can embody them after all but approximately and suggestively. Spirit and Truth are like the Lady …
George MacDonald—Unspoken Sermons

The Magnificence of Prayer
"Lord, teach us to pray."--Luke xi. 1. "A royal priesthood."--1 Pet. ii. 9. "I am an apostle," said Paul, "I magnify mine office." And we also have an office. Our office is not the apostolic office, but Paul would be the first to say to us that our office is quite as magnificent as ever his office was. Let us, then, magnify our office. Let us magnify its magnificent opportunities; its momentous duties; and its incalculable and everlasting rewards. For our office is the "royal priesthood." And we …
Alexander Whyte—Lord Teach Us To Pray