At the core, this meditation has no affliliation with any religion or spirituality. At the same time, it is not incompatible with religion or spirituality.
In fact, you can align the meditation with these concepts.
The meditation is a conscious + subconscious process. The subconscious mind responds to symbols. God is a very powerful symbol. In fact, an all knowing, all powerful creator is the most powerful symbol.
You can make use of these symbols in the meditation process.
For example, in hinduism, there are many gods and one example is God Ganesha. Ganesha is widely revered as the remover of obstacles, the patron of creativity and the god of intellect and wisdom. As the god of beginnings, he is honoured at the start of rites and ceremonies.
So if you are beliver in hinduism, you may probably pray to God Ganesha before you start the meditation. Your subconscious mind will then pick up on this symbol and will help you through the process.
Or if you follow Sikhism, one powerful symbol is Ek Omkar. So you may start with the biginning prayer or Mul Mantra which are the opening words of Sikh scripture. Roughly translated, "There is one god, truth by name, the creator, without fear, without hate, timeless in form, beyond birth, self-existent, (known by) the grace of the Guru.". If you are a Sikh, these are very powerful words to say before meditation.
Generally, the symbol of God is very pure and positive. So if you are a believer, incorporate this in the meditation process. This will set a positive mindset and will also guard against negative effects.
Meditation without symbols is different from meditation with symbols (such as God). Similary, when you medidate with symbols, the subconscious will pick up qualities associated with the particular symbol you choose.
For example, in hinduism, there are many gods. Different gods have different qualities. God such as Shiva is powerful but Shiva is also the distroyer, he lives away from people and is not very social. God Krishna on the other hand is much more social and is normally associated with practical wisdom.
So a meditation that starts with praying Shiva at the biginning of meditation is different from a meditation that starts with praying Krishna.
Different people respond to different symbols. For example, during childhood you are brought up to worship a certain deity, you might respond strongly (either positive or sometimes negatively) to that deity.
Different life situations also work better with different symbols. For example, if you are studying for exams, you might pray to Ganesha, since Ganesha is god of learning and intellect. If you are going through difficult life circumstances, you might pray to Krishna, since Krishna is god of practical wisdom.
So be mindful when you choose the deity to pray before the meditation. You can also change the symbol based on your life circumstances.
Meditation, with careful practice, will give you positive results. If you are praying to a deity, and since meditation is a suggestible state, then your subconscious will start developing attachment to the deity you chose.
We can see this association and attachment already within various religious sects. Though this is not a bad thing in itself, be aware that this might happen to you as well.