Many of us still separate our lives into our secular life and our spiritual life. One reason is that they believe "secular" means, "worldly," "not holy," or "not spiritual," and "Spiritual" means praying and going to church, e.g., giving "one hour a week to God." Let's take a closer look..
"Secular" means whatever pertains to space/time, i.e., to our everyday life here and now in this world, e. g., our education, our marriage and family life, work, politics, science, art, recreation, etc. All these things are spiritual, all are sacred and holy. All 168 hours of the week are sacred and holy.
We do not grow in holiness by separating ourselves from this world. Even contemplative monks live in lively and loving relationship with the everyday world. They love all people and all nature, and many work hard at farming, or some other occupation. We grow in holiness by making our everyday, space/time lives more orderly, just, peaceful, joyful, etc. (See the Spiritual Disciplines). And especially, by doing all things in love and even charity.
Our everyday life is the "raw material" of the life we will live in eternity. Just as we will not be destroyed after death, earth will not be destroyed. Our eternal life will be lived with others on earth--with everyone and everything changed beyond our imagination. The more fully and lovingly we live our lives here and now, the more fully and lovingly we will live our lives in eternity, and the more intense will be the love and glory we will give to God. We should not "waste" any of our heaven to come.
Vatican II is clear on the importance of making our everyday lives our spiritual lives. The language is a bit clumsy the the idea comes through:
They are mistaken who, knowing that we have here no abiding city but seek
one which is to come (cf. Heb. 13:14) think that they may therefore shirk their
earthly responsibilities. For they are forgetting that by the faith itself they are
more obliged than ever to measure up to these duties, each according to his
proper vocation (cf. 2 Thess. 3:6-13; Eph. 4:28). Nor, on the contrary, are they
less wide of the mark who think that religion consists in acts of worship alone
and in the discharge of certain moral obligations, and who imagine they can plunge
themselves into earthly affairs in such a way as to imply that these are altogether
divorced the religious life. This split between the faith which many profess and
their daily lives deserves to be counted among the more serious errors of our age.
The Church in the Modern World. No. 43