Psalms 11:4

The Lord [is] in his holy temple
Not in the temple at Jerusalem, which as yet was not built; nor in the temple of Christ's human nature; but rather in the church, where he dwells, which is an holy temple to the Lord; and which is an argument for trust in him, and a reason against the fears of men in the worst of times; see ( Psalms 46:1-5 ) . Though it may be best to understand it of heaven, the habitation of God's holiness, and which is the true sanctuary; and which the holy places made with hands were only a figure of; since it follows,

the Lord's throne [is] in heaven;
yea, the heaven is his throne; here he sits on a throne of grace, and here he has prepared his throne for judgment; and both this and the preceding clause are expressive of his glory and majesty; and are said to command awe and reverence of the Divine Being, and to inject terror into the wicked; and to show that God is above the enemies of his people, and to encourage the saints' trust and confidence in him; and are mentioned as a reason why David put his trust in him; and are, with what follows in ( Psalms 11:5 ) , opposed to the advice and reasonings of some of his friends in the preceding ones;

his eyes behold;
all men, and all their actions; he sees what the wicked are doing in the dark, what preparations for mischief they are making, and beholds them when they shoot privily at the upright in heart; he can turn the arrow another way, and cause it to miss the mark: his eyes run to and fro throughout the earth, in favour of those whose hearts are perfect and sincere. God's omniscience, which is denied by wicked men, who are therefore hardened in sin, and promise themselves impunity, is used by the saints as an argument to encourage their faith and trust in God, with respect to their preservation and deliverance. The Septuagint and Vulgate Latin, Arabic, and Ethiopic versions, read, "his eyes look unto the poor"; but this is an addition to the text not suitable to the context;

his eyelids try the children of men;
he tries their reins, he searches into their very hearts, and into the inmost recesses of them, and takes cognizance of their thoughts, intentions, and designs; and confounds and disappoints them, so that they cannot perform their enterprises.