Acts 12:5

Peter, therefore, indeed, was kept in the prison, and fervent prayer was being made by the assembly unto God for him,

2 Corinthians 1:11

ye working together also for us by your supplication, that the gift through many persons to us, through many may be thankfully acknowledged for us.

Isaiah 62:6-7

'On thy walls, O Jerusalem, I have appointed watchmen, All the day, and all the night, Continually, they are not silent.' O ye remembrancers of Jehovah, Keep not silence for yourselves,

Matthew 18:19

Again, I say to you, that, if two of you may agree on the earth concerning anything, whatever they may ask -- it shall be done to them from my Father who is in the heavens,

Luke 18:1

And he spake also a simile to them, that it behoveth us always to pray, and not to faint,

Acts 12:12

also, having considered, he came unto the house of Mary, the mother of John, who is surnamed Mark, where there were many thronged together and praying.

1 Corinthians 12:26

and whether one member doth suffer, suffer with it do all the members, or one member is glorified, rejoice with it do all the members;

Ephesians 6:18-20

through all prayer and supplication praying at all times in the Spirit, and in regard to this same, watching in all perseverance and supplication for all the saints --

1 Thessalonians 5:17

continually pray ye;

Hebrews 13:3

be mindful of those in bonds, as having been bound with them, of those maltreated, as also yourselves being in the body;

James 5:16

Be confessing to one another the trespasses, and be praying for one another, that ye may be healed; very strong is a working supplication of a righteous man;

Treasury of Scripture Knowledge

Summary

Peter therefore was kept in prison: but prayer was made without ceasing of the church unto God for him.

General references

Bible References

Prayer was made without ceasing, or, instant and earnest prayer was made

Acts 12:12
also, having considered, he came unto the house of Mary, the mother of John, who is surnamed Mark, where there were many thronged together and praying.
Isaiah 62:6
'On thy walls, O Jerusalem, I have appointed watchmen, All the day, and all the night, Continually, they are not silent.' O ye remembrancers of Jehovah, Keep not silence for yourselves,
Matthew 18:19
Again, I say to you, that, if two of you may agree on the earth concerning anything, whatever they may ask -- it shall be done to them from my Father who is in the heavens,
Luke 18:1
And he spake also a simile to them, that it behoveth us always to pray, and not to faint,
1 Corinthians 12:26
and whether one member doth suffer, suffer with it do all the members, or one member is glorified, rejoice with it do all the members;
2 Corinthians 1:11
ye working together also for us by your supplication, that the gift through many persons to us, through many may be thankfully acknowledged for us.
Ephesians 6:18
through all prayer and supplication praying at all times in the Spirit, and in regard to this same, watching in all perseverance and supplication for all the saints --
1 Thessalonians 5:17
continually pray ye;
Hebrews 13:3
be mindful of those in bonds, as having been bound with them, of those maltreated, as also yourselves being in the body;
James 5:16
Be confessing to one another the trespasses, and be praying for one another, that ye may be healed; very strong is a working supplication of a righteous man;

General references

Acts 5:18
and laid their hands upon the apostles, and did put them in a public prison;