It is highly advisable to pray before doing the Hour of the Passion or any other prayer. We must first ask God that our prayers be pleasing to Him and help us to rectify our intention when we offer our prayers to Him.
Therefore, if we desire our prayers to be highly pleasing to Our Lord and that many souls including ours, will profit from them, it is highly advisable to always read the “Preparation before each Hour”.
In fact, in the "Prayer of Preparation before each Hour" we say to Our Lord: "...And to please You more, I take your thoughts, your tongue, your Heart, and with this I intend to pray, fusing my entire being in your Will and in Your love." (The Hours of the Passion - Prayer of Preparation before each Hour)
By fusing ourselves in the Will of God and asking Jesus to pray in us with His same intentions and with His same love, our prayers will have the same effects as the prayers that Jesus did.
In the same way, we must always do the Prayer of Thanksgiving after each Hour. During Holy Mass, we pray: "It is right always and everywhere to give You thanks..." This is the reason why we highly recommend you to do this prayer.
With this prayer, we not only give thanks to Our Lord but we also ask Him to confirm our desire to continue doing reparation together with Him all day long and to participate in His Passion for the salvation of souls.
“... I have tried to follow You in everything; now, having to leave You to go about my daily occupations, I feel the obligation to say to You, “thank You” and “I bless You”(The Hours of the Passion – Prayer of Thanksgiving after each Hour)