Psalm 34:2

My soul shall make her boast in the Lord
Not in men, nor in any outward enjoyment, nor in any works of righteousness, but in the Lord; "in the Word of the Lord", as the Targum; in the Lord Jesus Christ; in his wisdom, strength, riches, righteousness, redemption, and salvation; in interest in him, and communion with him: and this is not tongue but soul boasting; and not flashy and selfish, but solid, spiritual, and hearty; and with all the powers and faculties of the soul; see ( 1 Corinthians 1:29-31 ) ;

the humble shall hear [thereof];
either of the deliverance the psalmist had out of the hands of his enemies; or of his blessing and praising the Lord for the same, and making his boast in him as the God of his salvation; or of both: of these humble ones, (See Gill on Psalms 10:12);

and be glad;
for such rejoice with them that rejoice, and are glad at heart that others share in the goodness and grace of God; and also because by such an instance of the divine power and kindness they are encouraged to hope that he will, in his own time, deliver them out of their afflictions and distresses also.