when did the christians 1st considor the holycross as their religious symbol?

Answer 1

after Christ died for our sins. It became the bridge from the Law to Grace and the one and onyl way to Heaven

Answer 2

At first it was the fish...
Early depictions on Jesus usually showed Jesus in the form of a shepherd carrying a lamb. Tertullian (140-230 CE), a Montanist heretic, commented in his essay De Corona: "At every forward step and movement, at every going in and out, when we put on our our clothes and shoes, when we bathe, when we sit at table, when we light the lamps, on couch, on seat, in all the ordinary actions of daily life, we trace upon the forehead the sign." This might be an early reference to individuals tracing the sign of the cross on their body.

The use of the cross as a symbol was condemned by at least one church father of the 3rd century CE because of its Pagan origins. The first appearance of a cross in Christian art is on a Vatican sarcophagus from the mid-5th Century. 11 It was a Greek cross with equal-length arms. Jesus' body was not shown. The first crucifixion scenes didn't appear in Christian art until the 7th century CE. The original cross symbol was in the form of a Tau Cross. It was so named because it looked like the letter "tau", or our letter "T". One author speculates that the Church may have copied the symbol from the Pagan Druids who made crosses in this form to represent the Thau (god). 7 They joined two limbs from oak trees. The Tau cross became associated with St. Philip who was allegedly crucified on such a cross in Phrygia. May Day, a major Druidic seasonal day of celebration, became St. Philip's Day. Later in Christian history, the Tau Cross became the Roman Cross that we are familiar with today.

The shape of the original crucifixion device is a matter for speculation. Sometimes, the Romans executed people on a Tau cross, sometimes on a Roman cross and sometimes on a simple stake. The gospels, which were originally written in Greek, use the word "stauros" to refer to the execution structure. (see Mark 15:21, Mark 15:32, Matthew 27:32, Luke 23:26, John 19:17). This appears as the word "cross" in all but one of the English versions that we have examined.†

Answer 3

After the Jesus Hanged on the cross

Answer 4

Some say it was seen in a vision by Emporer
Constantine of Rome. Which is why he converted to Christianity.

Answer 5

When they turned from the "other" cross. Its' called an {ANKH}
and it means the gift of {LIFE} So be warned my fair-weathered friend, we are in serious, treacherous waters.

Answer 6

after Jesus was crucified on the cross