Passage
How precious also are thy thoughts unto me, O God! How great is the sum of them!
How precious also are thy thoughts unto me, O God! How great is the sum of them!
Psalms 139:15 My frame was not hidden from thee, When I was made in secret, [And] curiously wrought in the lowest parts of the earth.
Psalms 139:16 Thine eyes did see mine unformed substance; And in thy book they were all written, [Even] the days that were ordained [for me], When as yet there was none of them.
Psalms 139:17 How precious also are thy thoughts unto me, O God! How great is the sum of them!
Psalms 139:18 If I should count them, they are more in number than the sand: When I awake, I am still with thee.
Psalms 139:19 Surely thou wilt slay the wicked, O God: Depart from me therefore, ye bloodthirsty men.
The verse centers on "precious", "thoughts", and "great". It is saying that the verse draws attention to "precious" and "thoughts", so its meaning should be read from those terms before moving to application.
The nearby context moves from verse 16's "Thine eyes did see mine unformed substance..." into verse 18's "If I should count them they are...", so "precious" and "thoughts" belong inside that flow. In Psalms context, the local focus is worship, trust, the LORD's kingship, and covenant mercy.
A plain takeaway is to answer the verse's own emphasis on "precious" and "thoughts" with trust shaped by these words, not by a vague optimism outside the passage.