Be cheerful, always cheerful

Nobody is happy on earth until he decides not to be. This is the way the path goes: suffering -- in Christian terms -- the Cross; God's Will, Love; happiness here and, afterwards, eternally. (Furrow, 52)

Servite Domino in laetitia! -- I will serve God cheerfully. With a cheerfulness that is a consequence of my Faith, of my Hope and of my Love -- and that will last for ever. For, as the Apostle assures us, Dominus prope est! -- the Lord follows me closely. I shall walk with Him, therefore, quite confidently, for the Lord is my Father, and with his help I shall fulfill his most lovable Will, even if I find it hard. (Furrow, 53)

A piece of advice on which I have insisted repeatedly: be cheerful, always cheerful. It is for those to be sad who do not consider themselves to be sons of God. (Furrow, 54) 

(http://www.opusdei.org.in/sec.php?s=310)