Ephesians 5:19 sing psalms, hymns and spiritual songs to each other; sing to the Lord and make music in your heart to him; 20 always give thanks for everything to God the Father in the name of our Lord Yeshua the Messiah.

For the director of music. A psalm of David. When the prophet Nathan came to him after David had committed adultery with Bathsheba.

1 Have mercy on me, O God, according to your unfailing love; according to your great compassion blot out my transgressions.2 Wash away all my iniquity and cleanse me from my sin. 3 For I know my transgressions, and my sin is always before me.4 Against you, you only, have I sinned and done what is evil in your sight, so that you are proved right when you speak and justified when you judge.5 Surely I was sinful at birth, sinful from the time my mother conceived me. 6 Surely you desire truth in the inner parts; you teach me wisdom in the inmost place.7 Cleanse me with hyssop, and I will be clean; wash me, and I will be whiter than snow.8 Let me hear joy and gladness; let the bones you have crushed rejoice. 9 Hide your face from my sins and blot out all my iniquity. 10 Create in me a pure heart, O God, and renew a steadfast spirit within me.11 Do not cast me from your presence or take your Holy Spirit from me. 12 Restore to me the joy of your salvation and grant me a willing spirit, to sustain me.13 Then I will teach transgressors your ways, and sinners will turn back to you.14 Save me from bloodguilt, O God, the God who saves me, and my tongue will sing of your righteousness.15 O Lord, open my lips, and my mouth will declare your praise. 16 You do not delight in sacrifice, or I would bring it; you do not take pleasure in burnt offerings. 17 The sacrifices of God are a broken spirit; a broken and contrite heart, O God, you will not despise. 18 In your good pleasure make Zion prosper; build up the walls of Jerusalem.19 Then there will be righteous sacrifices, whole burnt offerings to delight you; then bulls will be offered on your altar.

Meaning of hyssop?

The signification of “hyssop,” is external truth, which is a means of purification. It is said in Exodus 12:24 that they should “take a bunch of hyssop,” because “a bunch” is predicated of truths and their arrangement (AC 5530, 5881, 7408). That “hyssop” denotes external truth as a means of purification, is because all spiritual purification is effected by means of truths. For the earthly and worldly loves from which man is to be purified, are not recognized except by means of truths, and when these are insinuated by the Lord, there is also insinuated at the same time horror for these loves as for things unclean and damnable, the effect of which is that when anything of the kind flows into the thought, this feeling of horror returns, and consequently aversion for such things. Thus man is purified by truths as by an external means. It was on this account ordered that circumcision should be performed by means of knives or lancets of flint. “Lancets” or “knives of flint” denote the truths of faith whereby purification is effected, (AC 2799, 7044); and “circumcision” denotes purification from filthy loves, (AC 2039, 2632, 3412, 3413, 4462, 7045).

[2] As “hyssop” has this signification, it was therefore employed in cleansings, which in the internal sense signified purifications from falsities and evils, as in the cleansing of the leprosy, in Moses:–

The priest shall take for the leper that is to be cleansed two living clean birds, and cedar wood, and scarlet and hyssop, and shall dip them in the blood of the bird that was killed, and he shall sprinkle upon him that is to be cleansed (Lev. 14:4-7);

and in like manner “in the cleansing of a house, if the leprosy be in it” (Lev. 14:49-51). For preparing the water of separation by which cleansings were wrought, cedar wood and hyssop were also employed (Num. 19:6, 18); by “cedar wood” was signified internal spiritual truth, and by “hyssop” external; thus by “cedar” an interior means of purification, by “hyssop” an exterior one. That “hyssop” denotes a means of purification is very manifest in David:–

Thou shalt purge me with hyssop, and I shall become clean; Thou shalt wash me, and I shall be whiter than snow (Ps. 51:7)

where “to be purged with hyssop and made clean” denotes external purification; “to be washed and made whiter than snow,” internal purification; “snow” and “whiteness” are predicated of truth (AC 3301, 3993, 4007, 5319). That “hyssop” denotes lowest truth, and “cedar” highest truth, is plain from these words in the first book of Kings:–

Solomon spake of woods, from the cedar which is in Lebanon even unto the hyssop that goeth out of the wall (1 Kings 4:33);

where “cedar” denotes internal truth which is of intelligence; and “hyssop,” external truth which is of intelligence.

resource: Biblemeaning.info