How do we serve God? - Psalm 100 explains
(א) מִזְמ֥וֹר לְתוֹדָ֑ה הָרִ֥יעוּ לַ֝יהוָ֗ה כָּל־הָאָֽרֶץ׃ (ב) עִבְד֣וּ אֶת־יְהוָ֣ה בְּשִׂמְחָ֑ה בֹּ֥אוּ לְ֝פָנָ֗יו בִּרְנָנָֽה׃ (ג) דְּע֗וּ כִּֽי־יְהוָה֮ ה֤וּא אֱלֹ֫הִ֥ים הֽוּא־עָ֭שָׂנוּ ולא [וְל֣וֹ] אֲנַ֑חְנוּ עַ֝מּ֗וֹ וְצֹ֣אן מַרְעִיתֽוֹ׃ (ד) בֹּ֤אוּ שְׁעָרָ֨יו ׀ בְּתוֹדָ֗ה חֲצֵרֹתָ֥יו בִּתְהִלָּ֑ה הֽוֹדוּ־ל֝֗וֹ בָּרֲכ֥וּ שְׁמֽוֹ׃ (ה) כִּי־ט֣וֹב יְ֭הֹוָה לְעוֹלָ֣ם חַסְדּ֑וֹ וְעַד־דֹּ֥ר וָ֝דֹ֗ר אֱמוּנָתֽוֹ׃
(1) A psalm for praise. Raise a shout for the LORD, all the earth; (2) worship the LORD in gladness; come into His presence with shouts of joy. (3) Acknowledge that the LORD is God; He made us and we are His, His people, the flock He tends. (4) Enter His gates with praise, His courts with acclamation. Praise Him! Bless His name! (5) For the LORD is good; His steadfast love is eternal; His faithfulness is for all generations.

(excerpt from "Software for the Soul: Psalms for Everyone" - Click here for the link)

She described a scene from Temple times long ago:

The children skipped joyfully ahead of the adults, careful not to drop the warm bread they each carried in their hands. The smoothly polished white marble of the Temple reflected the gentle sunlight as the harmonies of the Levite choirs resounded throughout the courtyard. As the loaves of bread were gently placed upon the table, and the music of psalms softly filled the air, it felt as if one’s soul had already taken flight.

The Thanksgiving offering of bread accompanied by Psalm 100, was made during the time of the Temple in Jerusalem. It is the only offering which will still be made during the Messianic era. For even when the world is in a highly refined spiritual state, and there is peace on earth, we will need to give thanks to God for His many blessings. It is also a psalm for all people everywhere, and for all time.

Psalm 100, the Psalm of Thanksgiving, is recited daily in the Jewish prayer book. According to the Siddur She’lah and Ya’avits, each and every day people experience miracles whether or not they realize it.

Yet, Psalm 100, the Psalm of Thanks, begins with words of service.”

A Psalm of Thanksgiving.

Let all the earth sing

in jubilation to the Lord.

Serve the Lord with joy…”

What does it mean to serve God with joy?”

The word “serve” or “ivdu” is derived from the same root as the word for “slave” or “eved” in Hebrew. Service is not easy. As we go about our daily lives, the reality is we are all servants. This applies even to a president or king. No matter where in life we find ourselves, whether high or low on the social strata, somehow we are each serving someone or something most of the time. Yet, the psalmist sings: “Serve God with joy…”

When we are immersed in thoughts, speech or action, that as a result, cause us to forget about God, it is an indication that we are putting something above God; for truly there is cause to be grateful for His blessings each moment we are alive.

How do we serve God with joy?”

One way we serve God with joy is by serving others each day. It is almost as if there is a special “barometer” of joy inside each of us. When we go out of our way to help someone; when we pray for someone; when we study the words of the Torah; our joy increases. The very act of serving God brings an inner sense of joy.

In modern times, we don’t bring three loaves of bread to the Temple as the Levite choirs sing the Psalm of Thanksgiving. “ “Instead we bring the bread of our efforts. We bring service with joy.

And as we serve God with joy, this feeling of joy that we experience deep inside has a multiplying effect, much like the pebble that creates waves as it touches the water.

The goodness and kindness grows and multiplies as each person continues to add to this cycle of service and gratitude to the One who created the world.