How far will a ‘covering prayer‘ reach and how lasting of an impact does it make, at it’s full range?
It can go to all generations and circle the globe.
(CF John 17 for example)
For individuals though, where intimacy lacks, more pray-ers and prayers are required. ((where 100$ bills are absent, more 20$’s are required. Even more 10’s, 5’s, toonies and loonies. The smaller the denomination, (generally) the less the giver feels the loss. How, the giver feels the loss goes far towards the gift’s sacrificial, and thus worshipful, nature.)) How the pray-er perceives his prayer goes far towards the prayers effect and staying power. To pray for people, at a remove, is physically easier but much harder spiritually. One has to stir himself up to engage with both the Lord and the prayer’s intended recipient. Low level engagement doesn’t weigh much spiritually.
As with currency, so with prayer, as prayer is a currency of a different, higher, sort. The prayer has to cost the pray-er some energy, either as emotions felt, thoughts thought, or words spent; ideally, all of the above.
In that spending, of necessity though, something else in the pray-ers life is temporarily set aside and eventually needs to be made up for. It costs to be a prayer. But it costs like investing costs- the energy is gone but it builds interest clear into eternity promising rewards now and in the world to come. Your prayers, regardless of their weight, are never lost.