Passage
You know my sitting down and my rising up. You perceive my thoughts from afar.
You know my sitting down and my rising up. You perceive my thoughts from afar.
Psalms 139:1 Yahweh, you have searched me, and you know me.
Psalms 139:2 You know my sitting down and my rising up. You perceive my thoughts from afar.
Psalms 139:3 You search out my path and my lying down, and are acquainted with all my ways.
Psalms 139:4 For there is not a word on my tongue, but, behold, Yahweh, you know it altogether.
The verse centers on "sitting", "down", "rising", "perceive", "thoughts", and "afar". It is saying that the verse draws attention to "sitting" and "down", so its meaning should be read from those terms before moving to application.
The nearby context moves from verse 1's "Yahweh you have searched me and you..." into verse 3's "You search out my path and my...", so "sitting" and "down" 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 "sitting" and "down" with trust shaped by these words, not by a vague optimism outside the passage.