They were just some examples. The main point is if there is some action on our part in regards to those two particular temptations …it is good to use a very short rejection and then turn to something else. As you too noted…not to get entangled more into the temptation etc. The main way out of such temptations is flight…running away
The “I am a Christian” I took from the trial records of the early Christian Martyrs (who are very important to me…and in fact my wife and I use the phrase as part of the our daily renewal of our following as disciples…of our baptismal promises) (and example:
earlychristians.org/testimonies_martyrs/scillitan_saints.html). It sums up nicely ones baptismal life. A temptation comes against chastity…one reaffirms that “I am a Christian!” meaning…no way…I follow Christ! He is the meaning of my life…I am a Christian so I do not do such things…I know true life! And I will continue to walk in that life etc. Or if it is against Faith…well it is a simple profession of Faith. As is the “credo” which I took from St. Therese who during here great sufferings of temptations against Faith she would just right that word…even in her blood that she spit up from her TB.
The “No” could be in the heat of some temptations…as you turn to something else. But I would not get into repeating it too much…for then one can get into the “direct” fighting too much. Indirect …flight is best in terms of temptations against Faith or Chastity.
If your temped to other things…direct is often better. By acting with the virtue opposite to what you is tempting you. You are tempted to put off the task. Do it first. If you are temped to eat too much…fast abit. etc.