All that Abgarus could do to serve the Parthian cause was, first, to induce Crassus to trust himself to the open country, without clinging either to a river or to the mountains, and, secondly, to bring him, after a hasty march, and in the full heat of the day, into the presence of the enemy.

Both these things he contrived to effect, and Surenas was, no doubt, so far beholden to him.

But the notion that he enticed the Roman army into a trackless desert, and gave it over, when it was perishing through weariness, hunger, and thirst, into the hands of its enraged enemy, is in contradiction with the topographical facts, and is not even maintained consistently by the classical writers.
It was probably on the third or fourth day after he had quitted the Euphrates that Crassus found himself approaching his enemy.

After a hasty and hot march he had approached the banks of the Belik, when his scouts brought him word that they had fallen in with the Parthian army, which was advancing in force and seemingly full of confidence.

Abgarus had recently quitted him on the plea of doing him some undefined service, but really to range himself on the side of his real friends, the Parthians.