Jn 12
Then Jesus said to them, "A little while longer the light is with you. 
Walk while you have the light, lest darkness overtake you; he who walks in darkness does not know where he is going. While you have the light, believe in the light, that you may become sons of light."

O our Master, the King of all ages, to let Your face shine upon us, and the light of Your divine knowledge enlighten us. Grant us, O our Master, to be sons of light and sons of day, to pass this day in righteousness, chastity and good conduct, that we may complete all the rest of the days of our life without offence; through the grace, the compassion and the love of mankind of Your Only-Begotten Son Jesus Christ, and the gift of Your Holy Spirit, now and at all times and forever. Amen.
The Book of Hours - 1st Hr.