The teaching of Zen and other philosophies suggest being a witness, unattached, not thinking anything.
But Guru Nanak says everything is fruitless without name of God. What to do, being a witness or silently repeat the name of God? How to combine these practices? Many say, be one with name of God, but many others say that the Self is unattached to every experience, it is a solitary witness.
First of all: happy Mahasamadhi of Yogananda: he left his body on this special day, 61 years ago.
Arjuna asks a similar question to yours, in the Bhagavad Gita (12;1-5):
"Arjuna said: Between those who worship You with steadfast devotion, and those who concentrate on the Absolute, which is better versed in the yoga science? The Blessed Lord answered: Those who, with minds fixed on Me, are ever united to Me in pure devotion, are in My eyes the best versed in yoga. Those, however, who aspire to the Indestructible, the Indescribable, the Unmanifested, the All-Pervading, the Incomprehensible, the Immutable above all vibration, who have subjugated the senses, are even-minded, and devote themselves to the well-being of all—verily, they, too, attain Me.Those who make the Unmanifested their primary goal make the path more difficult for themselves. Arduous is that path for embodied beings."
In short: there are two main ways to obtain God, or Cosmic Consciousness: one is the way of Advaita Vedanta: nothing is real but the Eternal Self; be a witness, explore the non-attached formless Self. God is seen as same as the Self: the unmanifested absolute Consciousness.
The other way is Bhakti, the path of devotion, worshipping God, singing His name, loving Him, a God which can assume form, communicates with you, saves you, inspires you, being a Friend, or even a Lover, or a Heavenly Father or a Divine Mother.
Krishna in the above passage teaches that the devotional way is better suited for most people, saying that the road to the Unmanifested is "arduous". Why? What is needed on the spiritual path is the heart’s participation. In everything you do in life, if your heart is in it, your activity will be full of energy and enthusiasm. If the heart is missing, you'll get tired soon of anything, including meditation and the spiritual search. The personal approach to God is more likely to stimulate our heart. However, this is not a general rule: I know devotees who are deeply devoted, even passionate in their heart, in their search of the formless eternal Truth.
Actually Yogananda says (In Essence of Self-Realization) that a combination of both attitudes is the best way:
“There are two ways of approaching God in Nature. One is to separate the Lord from all His manifestations. ‘Neti, neti,’ is the saying in India: ‘Not this, not that.’ Something of that consciousness there must always be, lest one become trapped in attachment to form.The other way is to behold the Lord manifested everywhere. The first way, by itself, may be too austere for most devotees. The second way is much sweeter. Best of all is a combination of both."
Personally, before coming to Ananda, I meditated with a Zen technique (I was an atheist). But it became too dry for me. When I opened to the idea of a living God to whom I can sing, I did. At one point I sang Guru Nanak’s song "Oh God beautiful" and a little miracle happened to me. The Divine answers to our love, not much to our detachment, I believe.
So it is a personal choice, both paths (and practices) are valid. You may even combine them. How? By saying, "Finally speaking everything is Spirit, formless, the soul is a detached witness. But the path to get to that realization depends on the full love of my heart. Therefore I stimulate it as much as I can. Since the Eternal Spirit can take on any form for the devotee, I will love Him, sing to Him, pray to Him. After my prayers and chants, I practice techniques to still my mind. And after the techniques, in stillness I feel His presence, which I love with form or without form."
God bless you. May you feel His answer to your singing and praying,
PS. This was a somewhat long reply to your question… and it’s getting even worse: Here is a poem by Yogananda from his Praecepta Lessons (1934):
O Thou Mother of all conscious things,
Be Thou consciously receptive to my prayers.
Through Thee I know all that I know;
And Thou knowest all I know,
So Thou knowest my prayers.
And knowing and feeling Thee constantly thus,
I know Thou art I, I am Thou.
My little wavelet has vanished in Thee.
I know Thou alone existed;
And Thou alone dost exist now and ever shall.
Thou art impersonal, invisible,
Unseen, formless, omnipresent,
But forever I want to worship Thee
As both personal and impersonal.
By my devotion, I behold Thee
Sometimes as Krishna,
Sometimes as Christ,
Personal, visible and imprisoned
In the little space
Hidden within the temple of my love.
O, Invisible, just as Thou didst freeze
Thine unseen Infinitude
Into the sea of cosmic finitude,
So do Thou appear unto me,
Visible and living
That I may serve Thee.
I want to see Thee as the ocean of life
With and without the ripples
Of finite creation.
O, Creator of all things,
I want to worship Thee both as personal