In Catholic, Why do we make sign of cross on head, lips and chest before reading the Gospel?

Question:
Why we make a sign of cross on head, lips, and chest before reading the Gospel?
Answer:
The first and simplest answer to this question comes to us from the rubrics. The rubrics for the Mass are the teachings given to us in the Roman Missal and they tell us the structure of the Mass. They tell us when to stand, sit, kneel, respond, etc. They also tell us that we are to make the sign of the Cross on our forehead, lips, and heart just prior to the reading of the Gospel.
But this question is probably more about the “why” we do this. The answer is simple. This gesture of signing ourselves with the Cross is a way of praying, “May the Lord be in my mind, on my lips, and in my heart.” It is said prior to the reading of the Gospel as a way of prayerfully inviting Christ to come to us in these ways as His sacred Word is declared. The hearing of the Gospel must transform our minds, it must be confessed by our lips, and it must affect our heart. By heart, we specifically mean our will, affections, emotions, and passions.
So next time you sign yourself with the Cross before the Gospel ensure that it’s more than just an external gesture, make sure it is also a prayer and an invitation to Christ.