Blessed be the God and Father of our Lord Jesus Christ, who has blessed us in Christ with every spiritual blessing in the heavenly places —Ephesians 1:3

Notice how blessed, blessed, and blessing are all in the same verse? Are these three the exact same word? Not quite. They are all based on the same Greek word, eulogéō.

eulogéō made up of word parts:
• eú, “well, good”
• lógos, “word”
Basically to say good words. The act of speaking in favorable terms (praise). It’s the word from which we get our English “eulogy”

In Ephesians 1:3 this eulogéō takes the form of three different parts of speech. Paul used the adjective, verb, and noun for “blessing” all in one verse.

• Eulogētos: adjective
• Eulogēsas: verb
• Eulogia: noun

eulogētos: adjective

Means praiseworthy. Only used for God.

eulogēsas: verb

Therefore, He blesses by intervening. In Acts 3:26, God sent His Son to bless us, to intervene in our lives with what He planned to do for us.
—Spiros Zodhiates

Did you notice that the verse is not future tense but past tense. Blessed is in the aorist tense which speaks of effective action, completed in the past. It is not that God will give us but that He has already given us.
—Precept Austin

This God who is to be praised is the One who has blessed us. This is a verbal form (ho eulogesas) of the adjective “praise” (elugetos), at the beginning of the verse. The verb means ” to speak well of eulogize, extol”; here it means to “benefit, prosper.” This word is not used in classical Greek literature. For example, Zeus is not said to have bestowed any specific act of blessing on anyone. Rather he is said to have caused good luck or good fortune. However, the verg eulegeo is used over 400 times in the Old Testament, indicating that God bestows benefits to His children in every Age.
—Bible Knowledge Commentary (by Roy B. Zuck, John F. Walvoord, Louis A Barbieri Jr)

eulogia: noun

Eulogia (blessing) is not verbal wish expressed, but actual blessing conferred. The reader will notice the peculiar collocation of the three allied terms, eulogetos-logesas-logia, a repetition not uncommon in the Hebrew Scriptures, and found occasionally among the Greek classics.
—”A Commentary on the Greek Text of the Epistle of Paul to the Ephesians” (by John Eadie, 1861)

Christians have already received all their spiritual blessings and thus do not need to pray or wait for a so-called “second blessing” so prevalently taught among charismatics. God has provided everything needed at salvation to bless Christians and allow them to bless Him. Everything.
—Dr. D. Lance Waldie

The blessing in this verse works like this short paraphrase

The blessed God
blessed us
with all spiritual blessings

The important part is is foremost the first “blessed”. He is the source of all blessings. He blesses us.

Side-note: In “every spiritual blessing”, the “every” is “pas” meaning all, whole, every, without exception.

Repeating blessed echoes Jewish liturgy

“Bible Knowledge Commentary” points out Psalms that have multiple blessings.

Psalm 65:1–4

[1] Praise is due to you, O God, in Zion,
    and to you shall vows be performed.
[2] O you who hear prayer,
    to you shall all flesh come.
[3] When iniquities prevail against me,
    you atone for our transgressions.
[4] Blessed is the one you choose and bring near,
    to dwell in your courts!
We shall be satisfied with the goodness of your house,
    the holiness of your temple! (ESV)

Verse 1: God is praised.
Verse 4: God blesses people.

Psalm 134:1-3

[1] Come, bless the LORD, all you servants of the LORD,
    who stand by night in the house of the LORD!
[2] Lift up your hands to the holy place
    and bless the LORD!
[3] May the LORD bless you from Zion,
    he who made heaven and earth! (ESV)

Verse 1: God is praised
Verse 2: God is praised
Verse 3: God blesses people.

Esphesians 1:3 tells much about God’s blessings on believers

(a) when: eternity past
(b) with what: every spiritual blessing
(c) where: in the heavenly realms
(d) how: in Christ
—“Bible Knowledge Commentary”

It’s so real

• Adjective: The eternal God whose character is praiseworthy. Never-changing. Truly blessed.
• Verb: He has blessed us. It’s fact. It’s an action done. Complete. Given. It has happened.
• Noun: Blessing has actually done. Not a wish. But real.