Prayerfulness, which is one of the ways that religious people are celebrating the Passover and Easter seasons, was captured a few days ago by photographs from the Holy Land. Associated Press and Reuter-United Press International wired to their clients two unforgettable pictures of devout young men uniting their hearts to God through prayer.

In one picture, a black-bearded Jew who looks to be no more than 25 is reading a prayer book, which is cupped in his hands like a sacred vessel. In the other, a Moslem on his knees is bowing in a field, his head touched to Allah's earth while his thoughts ascend to Heaven.

Stunning beauty is in these photographs. But beneath them were the captions, and all the beauty was suddenly desecrated as if a golden altar was being smashed by hammers of hate.

The Jew was an Israeli soldier praying before going into a raid on March 21 on the Shiite Moslem Village of Humin in southern Lebanon. He was atop an armored tank. An arm rested on a four-foot double-barrel machine gun, a weapon that was no doubt to be prayerfully and skillfully aimed at the villagers in Humin. Twenty-three of them were to be killed that day in Israeli army raids on four villages.

The Moslem was a Shiite guerrilla. In the photograph, another guerrilla sits on a rock in the background overlooking a plain southeast of Sidon. He is keeping watch with a rifle. Both hands are holding it as reverently as his fellow guerrilla lays his arms and head on the ground in prayer.

A news story beneath these photographs told of the slaughter these children of God were a part of. A mass grave had been dug in Humin. William Claiborne wrote in The Washington Post that inside a mosque next to the grave, "Red Cross and civilian defense workers laid out the bodies of 13 young men, riddled with bullets, and wrapped them carefully in white sheets."

A guerrilla was quoted. He promised "to fight to the death," which will probably not be a time-consuming wait. Then, wanting to maintain a theological context, he said that the "Israelis have made it clear now: The war is not a political war. The war is religious . . . They are fighting us because we are Moslems and they are Jews." The area is Christian.

It isn't yet clear whose prayers God will be answering. At Humin, the Israelis can credibly claim that God's finger was on their triggers. Twenty-three dead as well as another 34 slain the week before is not on a scale with the battle of Jericho, but only the faithless would doubt the presence of Divine Providence in such a respectable body count.

The theology of armies and God is not a branch of religion much examined. During the Vietnam War, it was said that there are no atheists in foxholes because they all had draft exemptions by going to divinity school. The classic text on soldiers who pray is an essay by Mark Twain, "The War Prayer." The 150th anniversary of Twain's birth and the 75th of his death comes at a moment when more than 40 nations are at war, with nearly all the rest spending themselves into poverty for arms when their turn comes.

"The War Prayer," which Twain is said to have dictated in 1905, told of "a time of great and exalting excitement. The country was up in arms, the war was on, in every breast burned the holy fire of patriotism." Prayers were said in stirring phrases for "an ever-merciful and benignant Father of us all" to help the lads "crush the foe" and to grant to the soldiers "and to their flag and country imperishable honor and glory."

Twain is mocking the scene, but he moves from sarcasm to justified cynicism when he has "an aged stranger" enter the church and move to the pulpit. Let's cut the piety and fakery, was his message. Instead utter aloud the kind of prayer that is really in the heart.

The war prayer is honest in its hate: "O Lord our God, help us to tear their soldiers to bloody shreds with our shells . . . Help us to lay waste their humble homes with a hurricane of fire . . . Help us to run them out roofless with their little children . . . For our sakes who adore Thee, Lord, blast their hopes, blight their lives, protract their bitter pilgrimage, make heavy their steps, water their way with tears, stain the white snow with the blood of their wounded feet. We ask it, in the spirit of love, of Him Who is the Source of Love . . . Amen."

As Twain wrote and as Jews, Moslems and Christians keep proving, militarism couldn't flourish unless violence was done first to religion.