By presidential proclamation, Ronald Reagan is asking Americans to join Thursday in putting to work one of the most potent but neglected tools at their disposal.

We are referring, of course, to the power of prayer and to the designation of May 5 as National Day of Prayer.Though polls show 87 precent of Americans pray at some time or other, many do so only in church or at Thanksgiving and Christmas. Few do so nearly as regularly and persistently as the scriptures admonish us all to do.

Perhaps that's because many, realizing that God knows his children's thoughts, think they don't need to pray even though Christ himself prayed long and hard.

But the objective of prayer is not just to inform God and certainly it is not to change his holy mind; rather, it is to learn his will for us and to obtain for ourselves and others the blessings that God already is willing to grant but that are made conditional on our asking for them.

Blessings, of course, require some effort on man's part. Consequently, prayer is a form of work.

At a time when spirituality and unity are badly needed, it is fitting indeed that a national day of pray be set aside. Let us pray not only for ourselves and our loved ones, but also for our country and its leaders.

There's no better way for Americans to begin and end May 5 than on their knees. Then let's all make personal and family prayer a daily practice.