The word yoga is a Sanskrit word that can be derived from either of two roots, yujir yoga (meaning to yoke) or yuj samādhau (meaning to concentrate).
First, yoga meaning to yoke.
2,600 years ago, when observing the absolute devastation brought by God on Jerusalem and on His Temple, the prophet Jeremiah says:
The Lord is good to those whose hope is in him, to the one who seeks him;
it is good to wait quietly for the salvation of the Lord.
It is good for a man to bear the yoke while he is young.
Let him sit alone in silence, for the Lord has laid it on him.
Let him bury his face in the dust— there may yet be hope.
Let him offer his cheek to one who would strike him, and let him be filled with disgrace. Lam 3:25-30)
To Jesus Christ, to be yoked to God is like being a branch on His vine.
Jesus Christ says:
“I am the true vine, and my Father is the gardener. He cuts off every branch in me that bears no fruit, while every branch that does bear fruit he prunes so that it will be even more fruitful. You are already clean because of the word I have spoken to you. Remain in me, as I also remain in you. No branch can bear fruit by itself; it must remain in the vine. Neither can you bear fruit unless you remain in me.
“I am the vine; you are the branches. If you remain in me and I in you, you will bear much fruit; apart from me you can do nothing. If you do not remain in me, you are like a branch that is thrown away and withers; such branches are picked up, thrown into the fire and burned. If you remain in me and my words remain in you, ask whatever you wish, and it will be done for you. This is to my Father’s glory, that you bear much fruit, showing yourselves to be my disciples.” (Jn 15:1-8)
The yoke of Jesus Christ is easy and His burden is light.
Jesus Christ says:
“Come to me, all you who are weary and burdened, and I will give you rest. Take my yoke upon you and learn from me, for I am gentle and humble in heart, and you will find rest for your souls. For my yoke is easy and my burden is light.” (Mt 11:25-30)
Second, yoga as concentration (or meditation).
Forty years after God brought Israel out of slavery and oppression in Egypt with a mighty hand and an outstretched arm, Moses, the servant of the Lord, dies.
God says to Joshua:
“Be strong and very courageous. Be careful to obey all the law my servant Moses gave you; do not turn from it to the right or to the left, that you may be successful wherever you go. Keep this Book of the Law always on your lips; meditate on it day and night, so that you may be careful to do everything written in it. Then you will be prosperous and successful. Have I not commanded you? Be strong and courageous. Do not be afraid; do not be discouraged, for the Lord your God will be with you wherever you go.” (Josh 1:1-9)
Psalmists write about meditation:
Blessed is the one who does not walk in step with the wicked or stand in the way that sinners take or sit in the company of mockers, but whose delight is in the law of the Lord, and who meditates on his law day and night. (Ps 1:1-2)
I meditate on your precepts and consider your ways.
Though rulers sit together and slander me, your servant will meditate on your decrees.
Cause me to understand the way of your precepts, that I may meditate on your wonderful deeds.
I reach out for your commands, which I love, that I may meditate on your decrees.
May the arrogant be put to shame for wronging me without cause;
but I will meditate on your precepts.
Oh, how I love your law! I meditate on it all day long.
I have more insight than all my teachers, for I meditate on your statutes.
My eyes stay open through the watches of the night, that I may meditate on your promises. (Ps 119:15, 23, 27, 48, 78, 97, 99, 148)
The apostle Paul says:
Finally, brothers and sisters, whatever is true, whatever is noble, whatever is right, whatever is pure, whatever is lovely, whatever is admirable— if anything is excellent or praiseworthy— think (or meditate) about such things. (Phil 4:8)
May these words of my mouth and this meditation of my heart be pleasing in your sight, Lord, my Rock and my Redeemer. (Ps 19:14)