Some things are constant.
The kingship of Christ. Grace. The omnipotence of God. Gravity (at least on the earth’s surface outside of an anti-gravity chamber, anyway). The sunrise in the morning and sunset in the evening (or afternoon, in the Seattle winter).
Somethings are not.
One day there is dirt, the very next day, there are green bulb stems reaching out from the dirt to an impressive height of a full inch tall. One day, there are pink gums and one tooth in the baby’s smile, and the very next day, there is another tooth decorating her grin. One day, it doesn’t matter if the dog barks, the very next day, it makes the baby scared and causes her to cry, and look up at mama for comfort.
Things can change entirely in just one day.
For the things which are constant, we should hold on to them tightly and dearly, appreciating their ever-presence. Don’t run from God and doubt his ability; He is all-knowing and all-powerful – that will always be true. There ARE things which will always be true, but in the grand scheme, the things which are this way are few. They are big, but few.
For the others, we should not hold onto things too tightly, for something that is can change overnight into what will be. And both will have been true.