Psalms 4:9

In peace together, I would lie down and sleep If Israel were in peace together with me, I would lie down and sleep in confidence, and I would not fear any adversary or enemy.

alone in safety As (in Deut. 33:28): “secure and alone, the fountain of Jacob.” It is an expression of safety and tranquility, that he need not station troops with him.

In peace (בְּשָׁלוֹם - be-shalom) - without fear.

And the meaning of together (yachdav) – [refers to] the many [his followers], and he [David] with them.

And the word alone (badad) – [whether] with a Lamed [prefix] (le-vadad, as in the verse), or in its absence [badad], it is equivalent [in meaning].

And similarly the word in safety (la-vetach) – and [the form] betach also exists [with the same essential meaning]. And behold [in contrast, (Deuteronomy 32:12) says]: "Ad-nai alone (badad) did lead him." And it is correct [that badad in Deuteronomy 32:12 refers to] HaShem alone. And so perhaps here [the meaning is 'You alone' make me dwell]. Or, [going back to the verse's structure:] '[My followers were] together (yachdav) with me.' Or [perhaps taking yachdav and levadad together or focusing on the latter part:] 'I was alone (levadad).' And the meaning [of the end] is: You make me alone (levadi) dwell [in safety].

In peace together would I lay me down and sleep: – I was desiring their prosperity, and still, although they have done me evil, I desire that we may be in peace together, I and they, and that if I lay me down and sleep I may not have anything to disturb me from sleep, after they return to me.

For Thou, Lord, alone makest me to rest in safety: – for I am confident that Thou wilt grant my desire and wilt make me rest in safety with them. And the interpretation of alone (is): Thou, Lord, only canst do this, and in Thee is my trust and not in another.