Gideon Jura's first ability causes creatures to attack him if able. If, during the affected player's declare attackers step, a creature they control is tapped, is affected by a spell or ability that says it can't attack, or is affected by "summoning sickness," then that creature doesn't attack. If there's a cost associated with having a creature attack, the player isn't forced to pay that cost, so the creature doesn't have to attack in that case either.