What is the ruling regarding a Muslim youth who swore by the cross?

If a young man has pointed to the sign of the cross and sworn by it, intending to venerate it, then this is disbelief in Allah. However, if he pointed to the cross and swore that he would be of its people if he did such and such, then this is a grave evil, because the Prophet (peace and blessings of Allah be upon him) said: "Whoever swears by a religion other than Islam, then he is as he said," and "Whoever says: 'I am innocent of Islam,' if he is a liar, then he is as he said, and if he is truthful, he will not return to Islam safely." He must seek Allah's forgiveness and repent to Him with sincere repentance, and hasten to say: "There is no god but Allah," because the Prophet (peace and blessings of Allah be upon him) said: "Whoever amongst you swore and said in his oath, 'By al-Lat,' let him say: 'There is no god but Allah.'"